Shooting manual lenses on Pentax DSLRs

Pentax K10D + Takumar 135mm f/2.5

One of the best things about shooting a modern Pentax DSLR is having access to 35 years worth of wonderful K mount lenses- all with shake reduction! That’s a feature no other camera manufacturer can claim. The problem is that using these lenses effectively on a DSLR is somewhat of a black art that requires the camera be set up properly. Read on for step-by-step instructions of how I set up my Pentax K10D DSLR for use with a manual lens.

SMC Pentax-A 50mm f/1.7

Old K mount manual lens selection is a blog article all to itself. Rather than discuss the pros and cons of specific lenses, I’m merely going to group them into two major categories: “A” lenses and “M” lenses. A series K mount lenses (like the 50mm f/1.7 shown above) can be thought of as essentially manual focus lenses on a Pentax DSLR.

"A" setting on aperture ring

“A” series lenses have an “A” position on the aperture ring. Engaging this setting locks the aperture ring and allows the camera to control the aperture setting with one of the E-dials on the camera body. The camera can be shot in any mode (with the camera automatically adjusting the aperture setting as required) just like with a regular modern AF lens with the only difference being the requirement to manually focus the lens. Placing the aperture ring in any other setting than “A” essentially turns it into an “M” lens. More on that in a moment.

SR focal length setting

When using any manual focus lens you need to tell the camera what the focal length is of the lens being used to get the best SR performance. To do this, simply turn the camera off, mount the lens, make sure SR is ON, turn the camera back on, and select the focal length of the lens being used on the rear LCD when prompted. You can do this after the fact using the menu system, but the fact is you should always turn the camera off when changing lenses anyway and Pentax makes this process practically automatic (assuming you have the SR turned ON when you turn the camera back on). Another benefit of doing this is that the focal length you input here will be recorded in your shot EXIF data- making it easier to tell which lens you were using later.

If your manual lens is a zoom it seems there is some conjecture over what you should do. Ideally, you would input the focal length you are shooting at but that seems rather tedious. Most of the info I have read says you will get the best results by using the shortest focal length setting for your lens. I would agree with this but I also think that you should use the longest setting if you are shooting primarily at the long end of the zoom range. It only makes sense as the SR would need to move a lot more to compensate for the exaggerated movement of a long telephoto focal length than at a shorter one.

You won’t have to mess with the SR setting when you switch back to a modern AF lens as the lens will communicate with the camera and make the adjustment automatically. You will need to repeat this process anytime you mount a manual lens and/or cycle the power switch with a manual lens attached.

focus selector

Logic would dictate that if you are shooting with a manual focus lens you should switch the camera into manual focus mode and this is the case most of the time. When shooting in MF with a manual lens you will still get focus confirmation when your subject is in focus via the center focus point illuminating red briefly in the viewfinder, the focus indicator lamp lighting (also in the viewfinder) and the audible focus lock beep (assuming it is enabled). See below:

focus indication

From what I can tell, the camera will only use the center focus point with older manual lenses (A and M). You can select other focus points with modern AF lenses when in MF mode. I always use the center point, focus, recompose, then shoot anyway. But that’s just the way I roll. Dialing in accurate focus can be tricky as the range of movement of the manual focus lens’ focus mechanism and front/back focus issues can throw the focus sensor off. The focus indicator will often stay illuminated over several degrees of focus ring rotation (in-focus range). This can be especially frustrating when using fast lenses with extremely short depths of field while trying to achieve critical focus on a specific point of the subject. Trial and error with lots of high magnification LCD review is the best way to get it right. Each lens will likely have its own characteristics that will need to be learned. A good excuse to take lots of pictures :D Here’s an article covering MF technique.

Another focus technique with manual lenses is “catch-in-focus” or “focus trap.” With this technique you set the camera to AF-S mode, fully depress the shutter then manually dial in the focus. As soon as focus is achieved the shutter will release. Problem is that it will either fire at the beginning or at the end of the in-focus range (depending on which direction the focus ring is being rotated) and the actual desired focus point may be somewhere else within the in-focus range. Also, if you are shooting at the slow end of hand-holdable shutter speeds you can actually get what I’d call “focus blur” as you focus through the desired focus point while the shutter is open. I find the focus trap technique most useful when trying to catch action shots and/or when shooting at smaller apertures in bright light. I find it basically useless when shooting wide open and/or in low light.


Metering is another issue with manual lenses. With my A series lens the camera uses the metering mode selected on the dial (spot, center weighted or pattern). However, with my Takumar 135mm f/2.5 M series lens (pictured at the top of the page) the camera defaults to center weighted averaged metering despite the fact that the selector is set to pattern. The other thing is that the exposure does not lock when you achieve focus in MF mode like it normally does in AF mode (with any lens in MF). So, if you do like I do and focus, recompose then shoot, you will likely get a different exposure when you recompose then you did when you set the focus. In pattern metering mode with my A series lens I rarely find this to be a problem as the pattern metering seems pretty adept at figuring things out. However, I occasionally have to use the AE-L button in high contrast situations to get the desired exposure, especially with my M series lens. Spot metering is typically useless unless you use the AE-L function.

Another metering issue is a bit more complicated. It seems that the metering system in the modern Pentax DSLRs is not optimized for use with the older manual lenses. I have read a lot about this and still can’t quite explain what is going on. Bottom line is that you may need to adjust your exposure up or down depending on the combination of camera/lens/aperture/subject being used. When shooting my A series lens in Av mode (as I typically do) I generally dial in around +0.7 to +1.0 EV compensation at f/1.7. If I shoot at smaller apertures I can often back off this setting depending on the subject matter. However, I do pretty much the same thing with every lens I use on my K10D so this is an area where experimentation is definitely required (on a lens-by-lens basis).

Takumar 135mm f/2.5 @ f/8

At this point you have pretty much all the information needed to get started shooting with an older A series manual lens. However, there are still a number of things left to do before you can even take the first picture with an M series lens. After following the directions above for mounting the lens, inputting the focal length and changing the focus mode, you will likely be greeted with a locked up camera and the dreaded flashing “F – -” screen:


(Please excuse my cracked LCD cover. This camera gets a lot of use.)

Seems to me Pentax should have made this “F – - -” instead ;-) What this is telling you is that the camera can not control the aperture of the lens mounted. What you need to do is tell the camera that everything is OK and to let you have control of the situation. To do this you have to navigate to the Custom Function menu and change the “Using aperture ring” setting to “Permitted”:



I guess Pentax sets this to “Prohibited” by default to force newbies into researching the use of manual lenses on their DSLRs. Whatever. This is likely the single most asked question of first-time M series lens users on a Pentax DSLR. Do it once and you won’t have to change it again. While you are in the Custom Function menu, check and make sure that the “Green button in TAv & M” setting is at the default setting of “1″ (”Program Line”). More on this in a moment.


Now that you have done all of this, you should see something like this on your status display:


There’s still an “F – -” showing in the display but now it should be steady and not flashing and the rest of the controls (including the shutter) should now be operational. The “F – -” now only means that the camera doesn’t (and won’t) know what aperture setting the lens is set to. Now we are getting much closer to being ready to shoot. Before we do though, I need to cover another detail. And yes, you will get to shoot pictures eventually :D

Manual exposure mode

There were two surprising things for me the first time I went through this process with my first M lens. I eagerly tore open the box from KEH, mounted up my lens, selected Manual exposure mode and proceeded to peer through the viewfinder the first time in preparation for taking my first shot. Right off the bat, I was surprised that the aperture did not close down when I rotated the ring on the lens like it used to on my old K1000. It makes sense, keep the viewfinder bright for focus and composing and stop the lens down only when the shutter releases. This brought me to my next conundrum: there is no active exposure meter display with an M lens. All I could see was a shutter speed and that damn F – -:

M seres lens view

I was shocked. I thought for sure I’d have a nice little exposure bar graph in the viewfinder with which to dial in the exposure just like I do with my AF and A series lenses in Manual exposure mode. Of course, I realize now that if the camera is holding the aperture wide open all of the time, and it has no way of knowing what the chosen aperture setting on the lens is, it has no way of calculating the given exposure. Duh! After fiddling blindly with the shutter speed and aperture ring and getting a few horribly mis-exposed shots I knew there had to be a better way- either that or my old Tak didn’t work with my K10D. So, I got on the internet and did a little searching. That’s when I learned about “stop down metering” and the purpose of that little green button when shooting in manual mode.

Green Button

Here’s how it works. In Manual exposure mode, you select your desired aperture using the ring on the lens, the desired ISO via the LCD, focus, compose, and press the green button. The camera will then briefly release the aperture so that it closes down to the desired setting (read: “stop down”) and take a meter reading. It will then offer up a shutter speed that represents a neutral exposure reading for the scene. At this point you can simply take a shot, review the results and adjust the shutter speed up or down to achieve the desired exposure for the scene. You will have to repeat this process for each new composition until you get to the point that you can just calculate the desired exposure by eye- like we used to do with old manual film cameras ;-)

This use of the Green button for stop-down metering seems to be the preferred method for most Pentax DSLR owners using manual lenses. As is often the case with these sorts of things, there are other ways. For instance, by holding the optical Depth of Field preview function closed (the icon to the right of the ON label on the power switch shown in the photo above), you can manually stop down the lens. The camera will then display the traditional bar graph exposure meter for you to adjust exposure with like with an old K1000. While this works, I find it rather awkward to use as my shutter speed control has been re-mapped to the front E-Dial wheel. YMMV.


My preferred method for shooting my M series Takumar 135mm f/2.5 is to shoot in Aperture priority mode (Av). The metering functions just like it would with any other MF lens and I can use EV compensation like I normally would. The main potential drawback is that the lens is always shot wide open- despite what the setting on the aperture ring may be. For me this is less of an issue as I typically like to shoot wide open anyway. If I need to stop down for some reason I typically resort to the DoF preview method as I like to see the exposure meeter. It correlates better with what I am used to seeing through the viewfinder when I shoot my other lenses.

This is by no means a complete tutorial on using manual lenses on Pentax DSLRs. There are a number of nuances for different lens and camera combinations and countless permutations of old lenses, each with its own idiosyncorosies. I offer up this “guide” as merely an informational starting point to help clear up some of the mystery for anyone looking to give an old manual lens a try. Here is another excellent step-by-step guide for shooting manual lenses on Pentax DSLRs. Be sure to research your specific lens/camera combination for more detailed specifics. Be aware that there are some K mount lens variations that do not work with modern DSLRs for a number of reasons. Do your research! That being said, many older K mount lenses represent terrific values and often will outperform their modern counterparts. This is one area where “they don’t make them like they used to” can really be true!

"studio" set-up

Several people have asked so I added this shot of my “studio” set-up I used to take the pictures in this blog post. I used a Panasonic Lumix FX07 pocket camera with a custom WB setting and + 7/10 EV exposure compensation. Framing up tight in macro mode helps keep the kitchen out of most of the shots. While most of my studio shots thus far have actually been shot in a small studio I have access to at school, it’s often easier to just do this little kitchen set-up at the house. I’ve been doing this enough that I’m contemplating mounting a small retractable white vinyl window shade to the bottom of the cabinet for an instant pull-down seamless backdrop. That is if the wife will allow it ;-)

163 Responses to “Shooting manual lenses on Pentax DSLRs”

  1. 1

    Thanks for that clear explanation that clarified several points that I needed to work out


  2. 2

    hi, im using a pentax k200 and i have a 600mm mirror telephoto which is fixed at f8, so do i need to tell the camera somehow that its at f8??? i can get some pics if i change the iso to 400 but other than that i struggle for a clear pic?

  3. 3

    You do not need to tell your camera what aperture your 600mm mirror is. Just set your camera to aperture priority (Av) mode and manual focus and you should be good to go. Remember to set the focal length of the lens for the SR to work properly. One of the problems you are going to run into with this lens is camera shake. The long focal length will greatly magnify any camera movement causing motion blurred photos. The slow f/8 minimum aperture means you will need a lot of light to get decent results (bright sun). Hand held you probably need to be shooting at 1/250 second or faster. This means you will most likely have to crank the ISO up to get the shutter speed up. Otherwise, you can use a tripod and the 2 second self timer. Just make sure your subject isn’t moving :D

  4. 4

    Hint: Replace the focussing screen by a split-field one. It’s so much easier focussing with manual lenses!

  5. 5

    Thx, very detailed and helpful~~~

  6. 6

    Thanks Robert.
    I admire people like you who are so willing to post useful information for us “others” on the web. :-)
    Very useful to learn that in AV-mode the camera only shoots at biggest aperture. In my view it makes that mode pretty useless, i.e. if you want to get good quality pictures with your lenses (unless you really want a shallow depth of field). Most lenses need to be stopped down *at least* one F-step in order to render good sharpness and minimal distortion. Therefore, Manual mode is pretty much the only quality option. Unfortunaely, the Green button gives very unrelistic values (on my K10d); almost always on the slow side. There may be a pattern however, which can be helpful to know (that is I am correct; I was just (re)checking it on my Pentax-M 50:1.4). It seems that the Green-button value is pretty much correct in relative darkness (e.g. in a room where only little comes in); in a normally lit room it seems to me that you should 10X-increase the time, thus when the Green-button suggests 5 sec. you should select approx. 1/50 sec.; outside in a half-cloudy weather increase the speed by 20X (1/60–> 1/2000). So, in a bright sun the best try to start with would be a factor of 40.

    Two conclusions to make: 1) Using the M-mode is not for the hurried photographer; 2) With *practice* that might change :-)

    I hope this is helpful (excuse my English),


  7. 7
    David Russell:

    Does this guide apply equally to M42 screwmount lenses (with the proper Pentax adapter rather than “guaranteed work 100%” garbage from evilbay :P) as it does to K-mount MF lenses?

  8. 8

    I would say that if you are having to apply those kinds of multipliers to your Green button readings to get acceptable exposure then something isn’t right. My Green button exposure readings are usually very close on my K10D when using manual lenses that are either wide open or stopped down. Of course, the metering defaults to center-weighted so you have to adjust exposure for the scene, but that is not typically more than 1-2 stops. Reevaluate your set-up and do some static tests to make sure everything is set-up right and functioning properly.

    I can’t comment on M42 lenses as I have no experience using them. I suggest you search There are plenty of M42 users there :D

  9. 9

    Thanks Robert.
    After reading your response, I did a more formal testing, a comparison between two of my old lenses; the Pentax-M 50mm:1.4 and a Pentax-K 120mm:2.8.
    The results: The K-120mm worked almost perfectly with the Manual mode; hardly any exposure adjustments were needed at any light level. The M-50mm, on the other hand, behaved as badly as yesterday (I’m angry at it! urrgh!).
    The sense morale: Test your old glass before putting it to work on your digital camera.

    Take care, Baldur

  10. 10
    Sonja Penny:

    I am so glad I came across your website. I am new to taking pictures (don’t have clue on using the Pentax). I like it and just purchased a Pentax K100D SLR Digital. Im studying the manual. I also purchased a Quantary autofocus lens 70-300mm F4-5.6. We see a lot of deers, in our neighborhood, during the year; a few of them rome in our back yard. When I attached the lens to my camera I noticed in the viewfinder the F– was blank and the AV was blinking. The camera was telling me that a lens was not attached (but it was). How do I set my camera to accept that lens? Do I use the illustration you provided? What books are good for “newbies”? My alternate email is Thank you.

  11. 11

    Thanks for the note and welcome to the Pentax family! Most likely all you need to do is set the aperture ring on your lens to the “A” position (and make sure it locks in place). Also, be sure the lens is seated all the way. If you have done both of these things and you’re still seeing the F– message their might be something wrong with your lens. Hope this helps you catch a shot of those deer!

  12. 12

    Thank you, Robert, very useful and generous. It helped me to get started with my KM (known to you across the big sea as the K2000) and old M lenses. There are small differences in the required procedure. Typically, I only found out afterwards that the user’s manual of the KM actually contains some useful info on how to use old lenses. I thought Pentax wanted to discourage their use.

    I’m only just getting started, but I hope to get lots of pleasure out of my new KM and my old lenses, thanks partly to you.

  13. 13

    Excellent article. Thanks a lot for sharing all this information

  14. 14

    Hey Robert,
    thank you for this effort. Such a good read.
    I am about to buy the smc-a 50mm/1.2, and i want to test it in the store of a dealer.

    Maybe i did not get it from your article, but my question is:
    is there any way, that the “F–” will disapear or is it ALWAYS there.
    Will the aperture be in the EXIF?


  15. 15

    I’m envious of that 50/1.2! If you are shooting an A series lens and its aperture ring is locked into the “A” position you will see the aperture on the LCD & viewfinder and in the EXIF data just like any regular fully automatic AF lens. Enabling SR and setting the lens’ correct focal length is the only way I know of to get an A series MF lens’ focal length to show up in the EXIF.


  16. 16

    thx Robert,i hope it’s gonna work with the used lens i want to buy on saturday!

  17. 17

    I have followed your instructions which have been a huge assistance. I am using M series lenses, 45 – 125 f4, 55 f1.8, 135 f3.5, 200 f3.5 with a K20D. The results have been very good but I am having trouble with focus. It seems to be very hit & miss. Do you have any suggestions as to how I can improve focus performance. Is a split screen likely to assist?

  18. 18

    Manual focus on a DSLR can be quite tricky. ONe of these days I will write a detailed blog post about it. For now, here are a couple of pointers.

    The main problem is that the Pentax AF indicator illuminates over a fairly wide range of focus. You have to figure out where within that range that the lens you are using is actually in focus (and you have to do it for EACH lens as they may all be different). With my 50 1.7 I find that actual focus is achieved at the center focus point when the focus indicator lamp first lights as I transition from close focus to infinity. (My 135mm f/2.5 Takumar is somewhere in the middle of the in-focus range). The problem is with a split screen is that the image in the viewfinder does not always look sharp. In fact, if I focus to what looks sharp to my eye I usually am off by a fair margin.

    There may be a trick with your K20D that will help here. My understanding is that you can fine tune the focus point on certain lenses (front focus/back focus) with a K20D. It is possible that you can do some testing and make adjustments to your K20D to make all of your manual lenses more consistent. It is also possible that your K20D won’t recognize which manual lenses you are using rendering the focus adjustment useless. My suggestion is that you try the technique I described above and take a look at this article:

    I have a K10D which has no focus adjustment so I’m stuck with just trying to learn where the actual focus point is within the indicated in-focus range for each of my manual lenses. Shoot enough with each of your manual lenses and you’ll figure it out.

    Good luck and thanks for stopping by!

  19. 19

    Great article. My K10D will see more of my old A50 f/1.7 !

  20. 20
    Irena Leite:

    Thank you!

    I’d say, it is a complete tutorial for using a manual focus lenses on Pentax K10D. It conforms per 100% with my experience I have gained in a more than a half year use of mf lenses (although I have no experience with A lenses, all of mine are M).. I wish I could get all these answers when I have put on a mf lens for the first time. :) But I have managed to arrive where you are in tech regard. And I have to add that I have got used so much to using them that I have no out of focus shot (almost).

    The only difficulty is to shoot a subject that comes closer, you cannot get it into focus fast enough.. the only lens managing to keep a subject in focus has been smc pentax-m 28mm f2,8 lens (the most recent buy that I have enjoyed a lot, because you can advance with a camera very close to a person to get a nice portrait, the others require a plenty of room (long distance shooting), maybe an explanation of a conversion factor could be added to your tutorial).

    Besides this one I am using also these:

    Tamron Adaptall 2 80-210mm f3,8 tele macro lens (this one has became my fave walk around lens – very sharp and precise, great exposure, easy to focus, extends your creativity to macro shooting, if you find something tiny and nice while having a walk)

    Tamron Adaptall 2 70-210mm f3,8 tele macro lens (a newer version of the previous one, that originally has been purchased for Oly OM10 by my hubby)

    Makinon 135mm f2,8 portrait/macro lens (very nice silky portraits, a long distance needed or using a macro option, if there is no room available. I have got great scene shots with this one from my seat during the concert of my daughter, although I had to put on a CP to reduce the light accessing a sensor)

    SMC Pentax AF Zoom 35-70mm f2,8 lens (this is the first af lens with a motor (recquires 4 AA batteries) that pentax has made but it was discontinued right after, and I didn’t get it work, of course). It is really sharp, makes nice colors and some say tricky to focus, but it has been my walk around lens for a while and I have had no out of focus photos).

    PS. In addition I have 2 af lenses that I have bought with K10D as a double lens kit, but since I have seen the quality you can get with cheap mf lenses, i almost don’t touch them, only if I need a wide angle (another thing to be mentioned in tutorial is that you cannot get a wide enough angle lens due to the same conversion factor). Maybe someone can correct me, because technically I cannot explain the things better than it has been done here. Not my interest at all. :) I just feel ready to share my experience. long-term plan is about to get a few nice limiteds of pentax. Shooting only manual can be really tiring sometimes. :)

    Thank you for sharing!

    My best regards,
    Irena aka DigitalGal in online forums

  21. 21
    Jon English:

    Thanks for a very useful, well written article. I’ve been thinking about buying a Pentax DSLR to utilise my 30-year-old K mount lenses and accessories.(My lenses are actually the M series introduced with the MX and ME cameras, the M reputedly standing for “Miniature”. Lens nomenclature can be a little confusing.)
    These are great optics butI didn’t realise the issues involved with using them on a modern DSLR. Your article has certainly saved me possible disappointment and frustration. I’m not sure I want to go there yet.
    In the meantime, I’m going to stick with my digital compact camera (Nikon Cooolpix).

  22. 22


    How do u determine the DOF on a *ist DL and a K10d?? When I turn the on/ogg switch to the right the viewfinder turns dark..?? How can I determine the DOF in such a scenario? Also, when using the manual lens and the exposure graph kicks in and starts blinking- what should I do in that case to adjust the correct exposure(should I + or – the exposure)??

  23. 23
    Jay McMerrick:

    Thank you for a great article,it got me to get out a SMC Takumar 1:1.4..50mm and have a go on my K200D ,at least I could shoot,but now to experiment for best settings. I found a treasure…Jay.

  24. 24
    Rob Effinger:

    Seems to me that my old Edixa 1:1.9 50mm lens works with AV mode and setting the lens to Manual mode. I had to play with the EV stops, but it seems good!

    Great article, many thanks!

    Tomorrow I’ll try the Edixa 70-230 telephoto for fun.

  25. 25

    The best way to do this is to think of the whole thing as one giant trip to the gym. ,

  26. 26

    Great, great info. here.
    Bookmarking …….100% complete

  27. 27

    Great article, thanks

  28. 28
    Andrew Curry:

    Many thanks for a carefully written, lucid and practical article. I recently bought a new “old stock” K100d Super from Asda, of all places, reduced to half price! I don’t care about it “only” having six million pixels but love the way it’s built, the in-body shake reduction and backwards compatibility. Not being a wealthy man, but wishing to acquire extra lenses, your article gave me the confidence to search e-bay for suitable lenses to go with the 2.8 standard lens which once belonged to my father. I purchased a Tokina 70-210 A zoom which looks like new and a rare Kenlock 28mm 2.8 which is heavy and beautifully machined. With p and p they each cost about £10! The build-quality of these pre-digital lenses is astonishing.
    As you say, part of the fun is in experimentation and with digital instant review, exposure and focusing inaccuracies are easily remedied. The standard lens has a wonderful short depth of field (sometimes too short!) and I used it exclusively one day to take some portraits with lovely defocused backgrouds…your 1.7 lens must be really something! The 28mm becomes 42mm on the K100 which is close to the (expensive)lovely silver pancake lens Pentax make, so it’ll be interesting to spend a day playing with that.
    Isn’t it great having things slide seductively into and out of focus and reconnecting with aperture and shutter speed combinations?
    Keep up the good work.

  29. 29
    Mark Green:

    Robert thank you for the time you invested in making this guide. One of the main reasons I purchased a K10D was the numerous lenses I had stashed away with my K1000 and a Sears wanabe. Thanks again.
    Merry Christmas !

  30. 30
    Jonathan Wilson:

    Great artical – thanks!

    Strangely these techniques are not obvious or well documented (if at all) in the manual and would take quite some time to figure out unless someone told you about it!

    I have been experimenting with my Pentax-A 50 1.7 off the “A” position and I’m now not worried about using manual lenses. If I see a cheap one I like the look of I will now buy!

  31. 31
    Luigi Pasini:

    I tank you a lot, Robert, for this accurate article that is very helpful for me.
    I’ve recently bought a K10D, just because convinced I could use my older K-lenses, and I was completely disappointed when I saw that nonsensical and nasty F– indicator after mounting manual lenses!
    I really appreciate people like you who have the passion of shearing knowledge and information.
    Thanks again.


  32. 32

    First , thanks for leaving great instructions…lowered my blood pressure when I found this article. A few minutes of easy clicking the new kit lenses which are fine on the Pentax K-m and giving pretty good results with a bit of fiddling with the settings and then I reached for the too long redundant ,beautifully machined lenses of yesteryear.

    Pentax M range of lenses were stored for the last 10 years unused and not worth selling at peanuts prices and now they are back to life on the K-m digital glad I didn’t give them away!! The instructions and settings detailed above look fiddly when you read through all the steps, probably a couple of times to get your head round it, but after one evening getting used to the set up I am already finding within a few seconds in Manual or AV mode results are superb.

    Don’t be put off, if you’ve got some manual lenses they will work no problem plus the bonus of focus indicator, camera shake etc all apply to the manual lenses with no extra fiddling.

    I also had a sinking heart when the aperture ring didn’t seem to have any affect but one tip (Pentax 2000/K-m, not sure about others) is that the Av+/- button can be pressed to stop M mode. Either way the lenses do what they always did with a bit of new tech. thrown in to boost the performance you can’t go wrong . I estimate it took around 50 pictures to get the hang of it so just delete those and off you go and it really is only a few seconds once you have made the menu changes (only ever have to do this once!) and know the routine. Use the kit lenses and wallow in the old manuals when you have a bit more time and want to take something other than snaps.Top bloke, thanks again.

  33. 33

    thank you for a thorough explanation. I gotta quick question on setting the focal length. Would I have to take in consideration of
    that 1.5 multiplier rule for setting up SR? So for my 50mm f1.4 would I enter in 50 for the focal length
    or 75 (50 X1.5)? Sorry its a stupid question but I am just starting up with my k-x and bunch of my dad’s old M lenses :)


  34. 34

    I have my Pentax K-7 since July 2009. Today I got my Pentax M 50mm f1.2. I noticed that need what I adjust to put input focal length. I don’t know what number??? it say 8 to 800. huh. Can you tell me, please? Thanks.

  35. 35

    You enter the focal length of the lens being used into the SR settings. So, for a 50mm lens you select “50″. It’s still a 50mm lens regardless of the effective focal length ;-)

  36. 36

    That was a great article and very helpful to me as I am new to photography and I was straggling with just that problem.Many thanks

  37. 37

    “If your manual lens is a zoom it seems there is some conjecture over what you should do. Ideally, you would input the focal length you are shooting at but that seems rather tedious. Most of the info I have read says you will get the best results by using the shortest focal length setting for your lens”

    So it means if I have Vivitar 80-200 lens, then I have to select 80?

    P.S. Very good manual, it was very helpful to me, many thanks!

  38. 38

    Inga, in short, Yes. You would set your Pentax to 80mm when shooting your 80-200. However, I might suggest you set it to 200m if you are shooting at 200mm and see if you get better results.


  39. 39

    I thought I’d add one thing for K-x users. If you already use your Green button for something else, you can use the +/-Av button for stop-down metering instead. For example, I have my Green button programmed to change my shooting mode from JPEG (my default setting) to JPEP+RAW, which allows me to shoot RAW on a picture-by-picture basis without unnecessarily using up memory space for shots I know I don’t need it for. So I didn’t want to reset the function of that button every time I use my manual-focus lenses. Turns out I didn’t have to, as the +/-Av button directly next to the Green button will accomplish the same function for metering with an M-series lens.

  40. 40

    Hello Robert,

    Thank you VERY much for this tutorial, it is very useful – now I understand why I was getting the same exposure using my Rikenon 50mm f1.7 on my new K-x in Av mode (i.e. it was shooting wide open every time :-).

    The metering on the K-x, with this lens seems to work very well and it is easy to compensate for the slight underexposure.

    Joe’s tip (posted on March 5th) on using the +/-Av button instead of the Green button was very handy as well since I can now reset the Green button to my previous preference. Maybe an idea to add this into your main tutorial (if it works the same on other Pentax cameras)?

    Thanks again!

  41. 41


    I just a couple of words….you ROCK! I was swimming in a sea of manual just trying to get my camera to actually be able to take a picture…not sure why Pentax set the inital setting to “prohibited”…but I appreciate the trouble you took to explain a few things to get me to the point that I can actually experiment with my camera.


  42. 42

    Thanks Robert, Your guidance got me going with my old tele and K7 for nature shooting from my back porch. Wouldn’t want to pack it far into the back country (weighs too much ;-), when I,m ready for that I’ll be getting a new lens (maybe next b’day :-).
    Thanks again, Dale

  43. 43

    Quick question: I mounted a T-mount 500mm mirror on my K-x and can find no way to set the focal length as described above. Even though SR was on when I shut down to change lenses, it is off while the mirror is mounted. Comes back on when I change back. Any way to keep SR with the mirror lens?

  44. 44
    Bjorn Andersson:

    Thanks! I’ve bought a K-7 and your site has been a good help to me.

  45. 45
    Richard Kirkley:

    Thanks for this article. As I read it I realized that I had a Pentax 50mm 1.7 sitting on my lens shelf. I had picked it up on ebay a few years ago for $35 planning to use it to copy slides from my Spotmatic days. Ipromptly put in on my K20D and with your article on screen as a reference tried it out on everything in sight.
    My gosh it is a little gem. I will now resurrect all my M42 lens and take each of them for a spin. Should be fun. I feel like a kid again. I have bookmarked your other articles for further reading.

    Thanks again

    Dick K.

  46. 46

    YOU ARE THE MAN. Now I have to figure out what’s different from your camera to mine, an *ist DL and I can break out my Tamron 70-210 telephoto, even though its probably not going to be easy! Thanks Robert!

  47. 47


    First of all, thank you so much for this informative guide. I bought a Pentax 50mm M 1.7 off ebay mostly because of it. I have noticed very spotty metering with my K10d and I have found a lot of other people online who have experienced the same thing. It seems that the consensus to fix the problem is to install a new focus screen. I was wondering if you had experienced this issue and if you did in fact install a new focus screen. Thanks!

  48. 48

    Thanks for such an excellent guide. It has allowed me to grab a whole load of manual lenses off ebay and from friends and relatives. Now my lens collection included a Pentax 50 mm 1.7 which is amazing.

  49. 49


    Excelent work you’ve done here. I’ve bought two M lenses (50mm 1.7 and 28mm 2.8) and though I am having quite a bit of trouble with correct metering (impossible to achieve with the K10D at apertures wider than f4; this is a known issue), the results at wide apertures are stunning indeed.

    However, there is something that intrigued me in your tutorial; yous say: «While you are in the Custom Function menu, check and make sure that the “Green button in TAv & M” setting is at the default setting of “1″ (”Program Line”).» Now Pentax recommends setting this to «Tv shift», which makes sense: the camera stops down the lens, takes a reading and then sets the proper (wishfull thinking…) shutter speed. Is there any reason your recommended setting should work any better?


    M. Matos

  50. 50
    Dennis Fairclough:

    I find that my old manual Pentax lenses consistently focus behind the selected focal point. That is; in the viewfinder it looks fine, but when checking the images later they are always way out. For instance, when I focus on the eyes, the earlobes tend to be more in focus. Same deal with k10 and K20 Using the K20 lens adjust made no difference it seems. Have played with the viewfinder adjust, everything. This has been a constant irritation for me. By the way, am using f1.7 to f4 mostly. It is not just narrow DOP… the focal plane is just wrong somehow.
    Any ideas? Denisio

  51. 51

    Thank you for submitting these instructions. I have an two old Pentax cameras one with a screw mount the other bayonet. No where could I find instructions as to how to use my old lenses on my new DSLR but your instructions have been fantastic and I appreciate the photographs illustrating the steps I needed to take to make the lenses and camera functional. Now I feel really good about my new(ish)DSLR Pentax since I can learn to use it without buying masses of new lenses. Neither the new Pentax nor the old lenses need languish in a drawer and I can stop relying on those wonderful tiny digital cameras for great snaps and can return to real photography. How very kind of you to share your knowledge with millions of strangers.

  52. 52


    Thanks for the info. I recently bought a k-x for my daughter, I use a Canon 550D with MF lenses and I was relieved to read in your article about missing the exposure scale in M mode, but then disappointed with the solution. On the 550D you get the exposure meter in the viewfinder in M mode, you can adjust the aperture, the shutter speed and see the effect on the exposure scale until you get the aperture/shutter combi of choice. I miss that already on the k-x, I don’t understand how Pentax can call it manual mode when it suggests the shutter speed for you with the green button and having to constantly adjust aperture, press green button, to get the shutter speed and aperture combination I’m after, it’s finicky in the extreme compared to seeing a sliding exposure meter in the Canon 550D viewfinder.

    My daughters well used to shooting in manual mode, manual focus and exposure with old lenses on the Canon 550D, hope she gets used to this finicky mess. I couldn’t stretch to a 550D for her. :-(

  53. 53

    Hey thanks for the info.

    I have a 43mm 1.9 lens for my pentax K7 and I hate it. I cannot seem to meter correctly with it. I am always guessing. If it is F4 usually I set the EV balance to -1.0 r -1.3…. but if I go up to F8 or higher I have to set the EV balance anywhere from -3.0 to -5.0

    Any Idea what I am doing wrong?

  54. 54


    That doesn’t sound right. There are a lot of variables here, though. I need to know exactly what lens you have, what shooting mode(s) you have this problem in, and any other details about the settings and conditions you are shooting under if I’m going to be able to help. It could be as simple as a quick adjustment or as complex as a mechanical and/or electrical problem with your lens and/or camera…

  55. 55

    Found your site when I searched for info on manual focusing for Pentax K7. Fortunately everthing you explained for the K100 applies to it, so now my Astron 70-210 PKA lens (about $30 US) is suddenly so much more valuable! I was using the MF and the viewfinder focus indicator and got about 50% success. With “trap-focus” it is closer to 100%, even wide open at f4 in poor interior lighting (in my kitcen). So my thanks for the clear and concise instructions, it has made a positive impact on my photography ( and bank balance!).

  56. 56

    I have a Pentax K7 camera and a SMC Pentax M 50mm 1.7 lens. It will only shoot wide open at 1.7 as there is a lever that physically controls the aperture, on the mount side of the lens. When the lens is locked into position on the camera body the lever is forced to stay open regardless of the setting on the aperture ring. Have other people found this to be the case? Is there an adapter to remedy this or can I even saw off the lever so that the aperture can be operated via the aperture ring?

  57. 57

    Ok, Please disregard my last comment. I have just figured it all out. I am such an idiot, all the lenses have that lever. Sorry for wasting your time!

  58. 58

    many thanks for this excellent tutorial! I have a K-x and bought a couple of nice prime lenses on eBay (Pentax-A 28mm f/2.8 and 50mm f/1.4, as well as a fully manual Cosina 40mm f/2.5 pancake lens) and with the help you offer I am enjoying using them more and more. Of course I still use the kit zoom lenses, but shooting with the old, beautifully manufactured, prime lenses is a pleasure of its own.

  59. 59
    John Bessa:

    What I don’t get is this:
    I assume the film cameras worked like film cameras do, and the later models were computerized. So why couldn’t Pentax program the Kx to do just like the film cameras did, instead of having to make exotic hardware like a “little green button?” Presumably they still of the code that they put in the old cameras.

    Seems like there may be little green men floating around in heads of the Pentax people.

  60. 60
    jim r:

    Thanks for the guidance – I’ve picked up several Rikenon-P lenses recently, the “P” designation is their equivalent to “A” for Pentax. I also have some “M” equivalent, and have exposed them badly with the K-7; this article should provide me with the ability to do a better job.

  61. 61
    Jan (notsowise):

    I recently purchased a sears 60-300mm auto zoom. It has a M42 mount and the aperture ring has the letters PU on it. any idea what that might mean? Do I set up for a manual lebs? Thanks for all the information on this site!


  62. 62

    My K10D is broken and cannot read the info given by modern lenses. Camera puts the lens on the widest aperture. That means the camera is not usable anymore. Thanks to old screw-mount lenses I still can use my camera. I should say that I had a hard and long time to master using m42 lenses correctly on a K10D. When I read your article I was so disappointed that I did not find it earlier. You have done a great detail job here and I think it answers all questions which may arise in this project. Thanks for the great job.

  63. 63

    great article~~
    i have a pentax k-x myself with a manual prime lens (smc pentax-m 1:1.7 50mm) and have been having fun with it.
    2 things i’ve been wondering about this manual lens is:
    a) the DOF scale that says 22-16-8-4|4-8-16-22, what is this used for? i read something about the infrared f-stop for the red mark to the left of the 4. but is there any use for the other markings?
    b) the little yellow-ish icon/button-like thing on the manual lens, it’s like a light but never lights up haha.
    thanks again!

  64. 64

    Thanks, The people at Pentax should be strung up… how any company can claim use of every lens ever made without readily supplying the info needed borders on deceptive…
    Thanks again!
    PS. you know anyone looking for a couple LX bodies with winders?

  65. 65

    In the 13th photo you show (in the Display panel), the Metering bar. How are you acieving this? You also said ” check and make sure that the “Green button in TAv & M” setting is at the default setting of “1″ (”Program Line”). More on this in a moment.” Where is the more about this. I have been told by everyone that tv shift should be selected, not program line

  66. 66

    The metering bar in the top LCD is actually showing the exposure compensation adjustment. The camera was in Av mode when this photo was taken. As for the “more on this in a moment” part, I go on to explain the use of the Green Button for stop down metering. All the Green Button does is stop the lens down to the manually set aperture (on the lens ring) and then calculate the shutter speed to achieve “proper” exposure. I say “proper” because mine always tended to severe underexposure. Now, I typically only used this method when shooting in M mode. I’m not sure what happens in Tv or TAv modes as I never tried those and I no longer own this camera.

    Hope this helps!

  67. 67

    Fantastic article! So, I was telling my husband how my K-x was now working using that green button so the camera would actually see what I was stopping the lens down to….so he wants to see this lens off the camera. It’s a 100mm 2.8 prime manual lens, pentax brand. Of course you can see the aperture open and close as you turn the ring….he says…why can’t the little lever be taken off of the old lens entirely? Once you put that lens on the camera, it does indeed keep the lens wide open. So, he wanted me to post this question to you….can we remove the that little lever??

  68. 68

    It sounds like you have an A series lens which allows the camera to control the aperture. The lens will always be at it’s wide open setting to make the view through the finder bright. Set the ring to the A position and then adjust the aperture to a smaller opening (bigger number) on the camera. Look into the end of the lens and take a picture. You should see the aperture close down when the shutter releases. I believe it works similarly for non-A series lenses with the lever. The only difference is you have to set the aperture to the desired setting with the ring on the lens. Check it out before you remove the lever. If it’s what I think it is, the lever is a good thing!

  69. 69

    Hi there! It’s not an A lens, but you were right! I found that it did work the shutter correctly…I was so surprised! I’ve had problems using the manual lenses with an attached flash unit tho…any suggestions on that? Ha! I’m so glad we didn’t remove that lever! Thank you so much!

  70. 70

    Sorry, I rarely use flashes ;-)

  71. 71
    Sukh Grewal:

    Could you please advise me as to how to use my old
    K mount manual focus lenses which do not have the
    “A” setting  on my pentax k-5.

    Thank you

    S Grewal

  72. 72
    Mark H:

    Thanks for taking the time to write this….very helpful!

  73. 73
    jean o':

    you are Godsend. Love your explanations with pics. i would never understand anything without the pics accompanying them. i am the one reading the instructions while my husband was the one fixing the camera. now we will be able to get really good pics. thank you sooooooo much. now i am assured that we’ve made a good investment in this camera.

  74. 74
    jean o':

    i mean Godsent. Robert, thanks again. Pentax owes you :)

  75. 75

    Hello everybody,
    Just got an Auto Revuenon 1:3.5-4.5 35-100mm for my K-7. I followed step by step the indications from this topic (enabled the custom functions regarding aperture ring and green button, set to M shooting mode), but, unfortunately, still doesn’t stop down to the selected aperture. Am I doing something wrong? The lens mount I think is K type (no electric contact at all).
    Thank in advance!

  76. 76

    Thank you so much for this detailed explanation of stopping down the aperture with a manual lens. I’ve been using a manual lens with my K-7 and couldn’t work out why it was always at f2 – lovely for narrow depth of field, but limiting. Now I can do so much more with this very nice old lens!

  77. 77

    Hi! Thanks for the useful info, but I have a problem. I follow all the instructions with my k5 and manual lens, but it just stays wide open all the time. What am I doing wrong? The lens is petri 50mm f/2. Thank you.

  78. 78

    Thank you for making this all so easy for us.Good work !. You are a gentleman.
    “Hold your head high for you are worthy”


  79. 79

    Really,really helpful, thanks. But, are you sure that when you shoot in Av mode the aperture opens fully? I don’t understand. The aperture is set by the ring and what would cause it to open?


  80. 80

    Hi thanks for the informative article, I have a Pentax K110d which i now use with a Pentax M 1.7 50mm, so now I have a fast portrait lens. I have just fitted a Travos dual split focusing screen, bought of UK ebay for £12.00, it took 10 days to arrive from Hong Kong, excellent little kit which includes tweezers and latex finger socks. The instructions were a little basic, so i followed the instructions on the KatzEye site. It took 10 minutes to fit, and that includes removing it and putting it back in the right way up! Manual focusing is now fast and accurate, and it does feel good having a “proper” viewfinder again. My first SLR was a manual focus Yashica, and the nicest a Canon T90.

  81. 81

    Mounted my Tokina 35-200 onto my Kr. Works fine except I would like to have the “split screen” focus that the Tokina has instead of
    relying on the red dot and beep. Any way I can get that?

  82. 82

    I have read this article at least ten times, the reason was 9 out of 10 photos I took with K M50 f1.4 lens were looking not sharp.
    I thought was the lens back focussing problem, turned out to be my camera holding technique.
    When I pressed on the button to take shot , the camera moved a bit , so the not so sharp photos 9 out of 10.
    I discovered that all I had to do was use my left hand to give a little counter force to my right hand finger which is moving the camera a bit when I press the button,
    Now 10 out of 10 sharp.

    Thanks very much.

  83. 83

    There is a lever on A type lenses that actuates the aperture when in A mode. Otherwise, you get what the ring is set to all the time.

  84. 84

    Thanks Robert, excellent, clear explanation of a problem which I have been grappling with for months – namely the dread F–. Lens now happily working. Yours is a website I shall return to for further education.

  85. 85

    I have a K7 put one of my old manual lens on followed your imfo.. the f still flashes . but i can take photos. do you think i will get that f to stop flashing.??

  86. 86

    Fantastic guide! Just a tip – for some reason the Pentax K-x will do stop-down metering on manual aperture lenses which have a plastic ring. You have to use foil or something conductive on the little circular connection points on the camera.

  87. 87

    THANK YOU SO MUCH!!! You responded to a post I made on a pentax forum and directed me to this blog and I can’t thank you enough! THis is exactly what I needed to know and it’s laid out so easily to understand. From my totally visual mind I thank you a million times!

  88. 88

    Nah, not into using the flash if i can avoid it at all i do

  89. 89
    Jose Llorca:

    Thanks for this explanation. Mention my experience. I made several shots with my K7. Never modify the exposure system, ie always leave segment metering and autofocus, as with any DA or FA lens. With the M lenses in manual mode and using the green button to get exposure in general get on results of an exposure of 1 EV. In contrast with the Takumar, placing the diaphragm with the ring at the desired point in AV mode and got very good results.

  90. 90
    Tom Otto:

    I’m kind of surprised I haven’t read this on here, (unless I missed it) but this is a trick I learned with my k100d and M lenses to act as an A lens. Basically, you just can’t lock your lens all the way in place. I put my aperture ring at 22, put the lens on the camera and slowly fasten the lens while I’m looking through the viewfinder. When it starts to brighten, thats where I stop fastening turning the lens on the body. Now you can use the camera in aperture mode (av) and all of the f stops will work with the camera adjusting the shutter speed for you, just like an A lens.

    Maybe everyone already knew this, but I just had to share.

  91. 91

    Interesting! Thanks for sharing the tip.

  92. 92

    I believe the camera defaults to spot or center weighted metering when using the green button. That likely would result in different readings than what you would normally see with your DA and FA lenses.

  93. 93

    Glad I could help!!

  94. 94

    Not sure how it works on the K7. Check the Custom Settings menu. Look for the option to shoot with aperture ring.

  95. 95

    Tom Otto`s tip about using M lenses as A lenses works on my Kx too.
    My M 28mm 2.8 and 3.5 lenses just became A lenses. Now exposure compensation works too.
    Tom, you just made my day. Thank you, Tom and thank you Robert for the blog.

  96. 96

    Thank you so much for taking the time to explain the use of Manual lens on K10D.
    10 minutes reading solved several issues I had been having with correct exposure and focus.
    You made my month.

  97. 97

    Excellent article! I was really banging my head trying to figure out the flashing ‘F–’ !!!

    I do have a question, tho. I am trying to photograph coins… I’m not highly experienced with the camera, although i did take a class many years ago. I’m using a K10D Pentax with a Pentax 18-55 lens. I can get pretty good results with it, but still have some blur on those details. I want to kick it up a notch and get crisp, clear images of the coins. I’ve been looking, but must admit I’m not really sure what I’m supposed to be looking for ‘lens-wise’. I’ve seen some attachments that screw on the front that are supposed to help? What exactly should I be looking to get to get those ultra nice close up shots?

    Another thing is when I shoot a picture, on the camera screen, it looks fine, but when I bring it onto the computer, the image is dark and yellow… I’ve tried all kinds of settings, adjusting the white balance, etc. but everything is either blue or yellow when I transfer the images. Any suggestions on how to correct this?

    Thanks again for a great article, and hope you don’t mind me picking your brain!

  98. 98

    Hi there,
    I am planning to buy a 500-1000mm lens (manual focus) for my K-7. Do you think I can apply the tutorial steps to get a decent picture of the super moon this weekend?

  99. 99

    Supremely helpful, I was a bit intimidated at first glance, but I picked up a Asahi Takumar 2.5 135mm for a really low price and love the results already! Once I got the feel for aperture settings and the focus, I am getting some wonderfully crisp pics with vibrant color. Your green button trick works like a charm. Thank you for your time to write up this detailed description.

  100. 100

    I have a pentax k-r and a cosina 28mm f/2.8 manual focus lens, but with an ‘A’ on the aperture ring. When I set the aperture ring to ‘A’, everything is fine, except for the fact that in every shooting mode, the maximum aperture is f/4 (which could be a bug as that is the maximum aperture of my pentax da 16-45 zoom which I usually use). When the ring is set to ‘A’, it won’t let me select an aperture wider than f/4. Any suggestions?

  101. 101

    Thanks robert for yoour great guide! I’m using K-r with Pentax-A 50mm/1.4, Pentax-A 28mm/2.8 and Pentax-M 85mm/2. But I’m planning to get a mint Pentax Takumar(Bayonet) 135mm/2.5 just like yours if I’m not mistaken. I found one for £70 with built-in hood. I would love to hear your comments and thoughts about this lens. Should I buy it? Btw I love street photography, potrait, and landscape

  102. 102

    Thank you very much Robert, by following your comprehensive and detail instructions I managed to set up my K-7 in a quick and easy way and shoot the first test pics with my “new” SMC-M 50mm/1.7. Great job and thanks again! Greetings from Italy and may you always have good light for your pics!

  103. 103
    David H.:

    Your site keeps on giving after these years. I just got a Samsung Gx-1L for almost nothing. I have some old K lenses. with your help I am back in business.

  104. 104

    Thanks so much!!! I sure appreciate the info. :)

  105. 105
    Ken B:

    Thank you for the info. Approaching retirement and trying to get back into hobbies of “days of yore”. Have been finding lenses at thrift store for pennies on the dollar.After reading, just got my ist-D shutter to drop for the first time with manual lens. Looking forward to hours of enjoyment because of you!!! Thanks again….

  106. 106

    Excellent, Ken. Thanks for the note. Happy shooting!

  107. 107

    Great!!! Thank You!

  108. 108

    Just wanted to say thank you for this post. I recently got into the game of photography with a Pentax K-X. I bought a SMCP-M 50mm F2 lens and was unsure of how to set it up for use with the newer camera. Then I found this, and it worked like a charm, great step-by-step!

  109. 109
    John G. Krueger:


    I have a question about the lack of an exposure bar in the viewfinder when using Pentax “M” lenses and setting the aperture ring to “Permitted”. The only way that I can see it is if I turn the On-Off lever to the small circle icon to the right of the On icon. Trying to turn the shutter speed dial and keeping the lever turned proves to be less than appealing. I have used manual 35mm cameras throughout and thought the DSLR would function the same way, that with the information in the viewfinder. But that, apparently isn’t to be. Do you know of another way to get the exposure bar visible in the viewfinder without having to press other buttons on the camera?

    On other question. I have two discs. One is the standard Pentax Photo Browser 3 and Pentax Photo Laboratory 3 combined on the same disc, and the other disc is Pentax Remote Assistant 3. What is the second disc used for?

    Thank you for the information.


    John G. Krueger

  110. 110

    I just have a question. I love taking pics and I have a Pentax K-x digital. I bought this camera b/c we had previously had a Sears brand 35mm. All the lenses fit the Pentax. My question is this, I now have a Sigma 70-300 mm lens. Sometimes I cannot get the camera to snap a shot. I don’t know if it’s the batteries or something else. I did notice that when I use the large lens it really eats the battery. So, one day I just change the batteries and it started to snap the shots again. Yesterday, I had the larger lens on and it wouldn’t work. I put my smaller lens on and it worked fine. Any suggestions. Also, I’ve had the camera less than two years and recently it became stuck in manual mode, which I don’t mind, but I really get agitated when I can’t get the lens to work. I’m a little anxious about sending my camera back to the company for repair. Any suggestions?

  111. 111

    Thanks a lot for writing this up. I just switched to Pentax, and now have a K-30. I guess my major question regards whether aperture info will be communicated to the camera, and subsequently to the EXIF file, with each of the major Pentax manual focus lens lineages (K, M, and A). Also, for A-series lenses, is aperture communicated to the EXIF file if using the aperture ring? Using these older lenses was part of what attracted me to Pentax in the first place, and not having a complete EXIF file will bug me.

  112. 112

    I don’t believe that the aperture data is recorded in the EXIF data for M series lenses (lenses where you turn the ring) but it is recorded for A series lenses (lenses where you set the ring to the A position and set the aperture with the camera).

  113. 113
    Burnt Umber:

    Thank You!

  114. 114

    I got K30 yesterday and your blog helped me managed to use it on Pentax-A 35-105 manual lens. Your blog is very informative and the pictures look nice too. Really appreciate your effort. Thank you.

  115. 115
    Dan Dempsey:

    I used a K-1000 SE and a ZX-5n and had two lenses I wanted to use on my K100D.

    But the K-100D apparently has no way to preview depth of field…. so I guess that stop down metering is not possible. Is that correct?

    I have a Kiron 105mm f2.8 Lester Dine Macro lens that I would like to use on my K-100D.
    (I also have the Dine Auto Exposure Macro Light.)

    So far I’ve been able to take non-flash pictures wide open easily with the Kiron.

    I also have a Vivitar Series 1 70-210 by Komine … same results wide open works fine.

    Should I just be metering by hand without the camera or do I have another option?

  116. 116
    Dan Dempsey:

    (continued from above)
    I should point out that I’ve been working from the cameras reading at f2.8 (say at 1/250)
    and then changing the stop and time ( like f4 and 1/125) (or f5.6 and 1/60)
    This seems to give adequate results but is hardly suitable for some work.

  117. 117
    Dan Dempsey:

    Correction my Series 1 Vivitar has the “A” setting unlike the Kiron.

  118. 118
    Dan Dempsey:

    Never Mind… (I found it)
    I finally got the K-100D set to “Optical Preview” the default is Digital Preview.

    On my K-100D it is found by…custom => Preview Method => Optical Preview.

  119. 119

    I have purchased new pentax K7 and have my old SMC Pentax M 1.4 50mm. Can you provide step by step photos for the use of my old lens?

  120. 120

    I’m sorry, Raman. I have never used a K7. It has a Green button so I’m assuming the steps would be quite similar to what I outlined in my article. If not, try the website.

  121. 121

    Dude!!! Thank you soo much

  122. 122

    I am new to photography… I got a K20D .
    Problem is that whenever I click any thing without popping up the flash, image comes blurred but it comes perfect with flash on. I guess there is some setting problem. I tried with pentax DA 28-55mm, FA 28-80mm and Sigma 28-135mm. But result is same every time .
    I’ll really appreciate if u can help me regarding this.
    Thanks in advance

  123. 123

    Thank you for the help. I am new to photography and just purchased a K50. I also purchased a lot of 12 lenses from Ebay that are compatible with Pentax cameras but are older off-brand lens. This article helped me to use these lens and now I’ll be able to use them as learning tool. Thank you for the in-depth descriptions, pictures and explanations.

  124. 124
    Saradindu Bose:

    Its a wonderful write up. I am also using Pentax k10d. Hope to try my old MANUAL lenses from ME SUPER.
    Saradindu Bose Kolkata India

  125. 125

    Very helpful! Thanks for the thorough and entertaining tutorial. :-)

  126. 126

    Just getting into photography and have picked up a K1000 and three lenses for £60, so for that I am fortunate, but the real bonus is coming across this website!!.

    Very informative blog and some great information………………….keep up the good work!! :)

  127. 127
    C Moore:

    Thanks for the info on the M series lenses. I have a ‘pancake’ M that I struggled with and guessed on exposure. It seemed easier to put an adapter and a screwmount lens, but now I see how to stop it down. On the new K-3 (just purchased) the green button can’t be programmed to stop down the lens, but the Raw button can.

  128. 128
    Rob W:

    ‘Tom Otto:
    February 5th, 2012 at 5:16 pm

    I’m kind of surprised I haven’t read this on here, (unless I missed it) but this is a trick I learned with my k100d and M lenses to act as an A lens. Basically, you just can’t lock your lens all the way in place. I put my aperture ring at 22, put the lens on the camera and slowly fasten the lens while I’m looking through the viewfinder. When it starts to brighten, thats where I stop fastening turning the lens on the body. Now you can use the camera in aperture mode (av) and all of the f stops will work with the camera adjusting the shutter speed for you, just like an A lens.

    Maybe everyone already knew this, but I just had to share.’

    Many thanks for your blog, Robert.

    I have a couple of ‘M’ lenses and have struggled with the metering but have just read Tom Otto’s post and it has made a world of difference.

    Metering is now consistent and I have auto ISO functioning as well as the metering functions(Spot and centre weighted any way) No need to stop down- used in AV mode the camera selects speed without a problem. It was a bit of a leap to not lock the lens down, but on a small prime it is fine, (but be careful to twist the right way, I nearly ‘lost’ my 50mm)

    Anyway, many thanks to you (and Tom)

    Regards, Rob

  129. 129

    A great article I have found with a lot of google search.I have 30 years back Pentax Super Program Film Camera with A Series 50mm 1.4 lens.Let me try it once again with K10D.

    My sincere appreciation to your best work.

  130. 130

    Many thanks!!

    I was very disappointed when I got Pentax-M 50 f/2 for my K-5.. Thought it was broken, but then I’ve found Your webpage :)

    Easy read………

    Keep up good work !!!

    Best regards

  131. 131
    Christos Pastelas:

    All the posts were very informative but somehow confusing. I owned a Pentax ME Super and a Z-1 and I have 3 SMC-M lenses (28mm F:2,8, 50mm F:1.4 and 75-150mm F:3.5-4.5 (also a 28-80 FA with the focus selection button broken). Currently I don’t have a DSLR.
    My question is: Is it worth buying a PENTAX DSLR just because I own these 3 lenses or look to other DSLR brands (eg, CANON) or even a mirror-less camera (such as the FUJI XT-1 or the SONY A6000)? It seems to me that my 3 lenses will be of very limited use, so maybe I should make a fresh start?

  132. 132

    I think you could get some use from your old Pentax manual lenses if you purchased a modern Pentax DSLR. It’s hard for me to say whether you should buy a Pentax DSLR, another brand’s DSLR or a mirrorless camera. Personally, I can tell you that I have tried them all and have settled on a Canon 6D as I prefer the way full frame sensors render images. A full frame Pentax DSLR would truly be wonderful with your old lenses, but alas it is not an option.

  133. 133

    Robert. many thanks for all the info on your site. As an old Pentax man I have a lot of gear, including an smc 1:4.500. Now using K10. Thinking of upgrading and undecided between a complete new Canon set-up or a newer Pentax as I could not get the old lenses to become compatible with the DSLR (Don’t tell me, RTFM) Thanks to your site,(now in ‘My favourites’ the dithering is over and its going to be the K5. Not cheap, but you saved me a bit as I have now learned to use the old SMC lenses and won’t need to buy new. Again, many thanks.

  134. 134

    Excellent article, but there is one bit of critical info that was left out. This can trip up people who try to follow your directions.

    For non-A lenses, the lens mounting ring MUST be bare metal. The Pentax DSLRs sense the mounting of a non-A lens because this ring shorts out the camera’s electrical contacts. If the lens has a plastic ring (or painted metal), it will not work unnless the contacts are shorted. You can either sand off the paint, or add tin foil to short out the electrical contacts – then it will work as you described.

  135. 135
    Stephan Kuhn:

    Much simpler on a Canon: set to Av, set aperture on lens as required for DOF, focus on zoomed-in live view, shoot. Only with poorly-lit subjects do you have to include opening aperture to wide, focussing, then stopping down. Canon meters automatically.

  136. 136
    Michael Wilkinson:

    Thank you, Robert. This was really helpful. I learned some stuff on the Pentax Forum and on the Ricoh site, but this is by far the clearest, best explanation I have found yet. Many thanks….now hopefully I can do the classic old lenses some justice.

  137. 137

    I had three old Spotmatic M42 lenses which I had written off until I bought a K30 and an adapter ring. Now I have a modern DSLR which takes perfectly fine pictures. I am trying to get the catch in focus to work. I have enabled the catch in focus and set the lever to AF-S and the dial to AV. However the shutter always fires when I press the button irrespective of the focus. Is there anything else I can try?

  138. 138

    Hi Robert,
    What a fantastic article you have written!
    Can you please tell me about the depth of field conundrum I have with my Pentax-M 50mm 1:1.7 lens and K10D. I find it impossible to focus at long distance (infinity) and the depth of field is extremely shallow – even at f22 at close distance. Reading this article makes me think there is something wrong with my camera ie misaligned sensor or something because the the view from the viewfinder seems OK. I have followed the focussing instructions in your article but still unable to get a good result. The lens itself is in perfect condition.
    Any suggestions?

    Many, many thanks.

  139. 139

    Unfortunately I’m not really sure what’s going on with your lens. I doubt the problem is with your camera. It’s possible that your M lens is not stopping down correctly when you manually adjust the aperture. Other than that I’m afraid I can’t offer much more.

  140. 140

    I don’t think catch in focus works with adapter rings since there is no communication with the lens.

  141. 141

    Excellent. Thank you!

  142. 142

    the best article I’ve ever read on shooting manual lenses on Pentax DSLRs!
    this help me a lot first time I tried with my camera, thanks

  143. 143

    Excellent article! Thanks so much for sharing this detailed information. I was trying to figure out why I was getting no exposure bar graph when using an old M lens on my K3. Now I understand why, and what to do to wrk around it! Thanks again!

  144. 144

    Finally, someone who knows what they are talking about and gets right to the point, THANK YOU so much for the clear and concise information, I love shooting with older Pentax glass and this had been a big help to me ! (:>)

  145. 145

    You stated: “Spot metering is typically useless unless you use the AE-L function”.
    I have the K3 and have been wondering how to ‘trick’ the camera in spot metering. My previous dslr’s, I can meter off anything, hold the button half down and recompose to “trick” the camera to expose how I would like it to. (example: silhouettes)
    Can you explain how to do this with the K3? Do I just depress the AEL button until I take the shot?

  146. 146

    Sorry Laurie, I don’t have a K3 so I’m not sure how it works.

  147. 147

    I recently purchased an older manual lens (TAMRON ADAPTALL-2 80-210mm, 103A with Pentax K.M mount). I have gone through all the steps recommended by Pentax and your article to set the lens up on my K-30 camera, and the lens works without any issue. My trouble is appearing when I shut the camera off and turn it back on with the lens still attached. The camera appears to be off, but when looking through the viewfinder, there is some info displayed at the bottom, including the flashing F–.

    Once this happens, the camera is essentially frozen until I remove the battery. Nothing works at all. The power switch won’t even turn it off at this point. If I remove the lens at this point (once the battery has been removed and I power it off with the switch), the mirror is partially opened…

    I know the camera you wrote about in this article isn’t the same model, but ANY help with this issue would be greatly appreciated.


  148. 148
    j taylor:

    Bought my first dslr in Feb,Pentax K-50 after owning an older bridge for a few years!
    Just trying out the Asahi 50mm 1.7, after the initial heart attack issue of F–…came across you’re advice and had it sorted in seconds thanks to your ‘custom app’ settings advice…thank f—. Haha, cheers!!

  149. 149

    I have a pentax k-x. I bought a 50mm “A” macro lens. I also picked up a ring flash to get better results in my photographs. My problem is that when I set my camera on M the flash won’t fire. Do I need to make an adjustment in the camera. I manually set the f-stop at F22 and my shutter speed at 1/250. I’m wondering if I need to turn off my pop flash?

  150. 150

    I have a K-50 Pentax and I’m still learning ! your Page here helped me SO much !
    I really appreciate the information. I applied a used 70-210 lens and started clicking
    pictures with your help here ! Thank You !

  151. 151

    Hi, just looking for some help with my Pentax k-r z please, when I change back to an autofocus lens my camera shots are all dark, the only way I can get the camera to operate normal is to take a lot of shots in continuous burst mode then everything is fine in single mode, my camera has also started to make a triple clicking thud sound on startup?

  152. 152
    Andrew Wylie:

    You don’t mention (no-one ever does) that you can’t use the built-in flash with old lenses – the camera does not know the aperture so it uses full flash power and your photo is a white-out. The only solution is to use a separate flashgun where you have to set the distance etc :-(

  153. 153
    Phil Christie:

    Using an old ist-d, still takes great photographs despite being only 6MP. Used a 50mm 2.0 A at a friends wedding and it worked great. Using my Tamron aspherical 50-200 on an electronic converter isn’t working and I’m about to blow a gasket!

  154. 154

    This definitely got me off the starting blocks. Being a beginner anyway I got my first manual focus lens as a present, Opteka 650-300mm and just like you ripped it out of the box, connected it, and peered through for my first shots. Here I am a couple of days later doing the research. Very helpful. As you mentioned there will be some differences with lens and camera combinations. I’m using a Pentax KS-1 but this read has been extremely helpful.

  155. 155
    Hal Saunders:

    Any idea if there is a way, with a more recent Pentax like a K50, of having it always display the exposure compensation bar? On my old Canon it was a doddle to use this as a defacto light meter, and do I ever miss it.

  156. 156

    Thanks for the article. However i do manually control the aperture of M lenses by simply cutting the aperture lever.

  157. 157
    Alec Blyth:

    Hello Robert,
    I have been shooting Pentax DSLRs for a few years now. I have several vintage lens both Pentax K and 42mm. I have periods of using my modern lens then return to the manual ones. I am constantly reading your article. Thank you so much for making it so comprehensive and user friendly. It must have taken a relatively long time to produce. Many people will have benitfitted from it.

  158. 158

    Thank you so much for a very clear explanation, I was already thinking I shouldn’t have bought a Pentax-K lens for my KS-2, haha

  159. 159
    Rob Fuchs:

    Thanks for all the good information. I picked up a early 1980’s Vivitar Series 1 70-210mm F2.8-4 (Cosina) and it has the “A” feature. Initially, this lens had the Ricoh Pin, but I removed it. The lens does not have the long flange. I can mount the lens on older Pentax film cameras with autofocus features (I used an old ZX-30 to test the lens), but I cannot mount it on my new K2S digital. It seems to get fit, but can’t be turned and locked into place. I completely removed the flange and it still will not turn into place. Has anybody had this issue with Cosina or Vivitar lenses?

  160. 160

    Hi, I followed your amazingly comprehensive instructions and put my Tamron SP macro-zoom lens on my K10D camera and the window came up asking for the focal length but the lowest number the camera would show as a choice for focal lengths was “8″ and my lens says “1:3.8-5.4″, not even near that “8″. Is there some other was of sneaking in the news to my camera that the lens has a lower number? Or will “8″ do for shooting, even though it is quite a bit higher?
    Thanks for all the info you gave on different ways of being out and in Manual.

  161. 161

    I went ahead and tried the “8″, but the camera continued not to work in the same way: Sometimes the shutter button will depress, most times it will not. Sometimes I have to keep it pressed for 5-10 seconds or forever and then it may/probably won’t finally shoot. Back when I first tried this lens (Tamron SP macro-zoom) on my K10D, it worked great for several shooting expeditions, then suddenly quit cooperating and shot sporadically, then I could get maybe one shot per outing, making it pretty much non-operative.

  162. 162

    I have a Pentax K-7 DSLR that is working perfectly. I wanted to try a lens on it that I was told would work with my camera. Apparently, I should not have tried it.
    The lens is a Sears 135mm f:2.8 Macro Telephoto lens. Now I cannot remove the lens. Nothing appears to be damaged, just that it does not rotate far enough (with lens unlock button pushed) to disengage and come off. One post said to put it in manual focus mode, and try it. No success. I also saw posts indicating that the use of a feeler gauge (.005″) at the 5:00 position between the lens and the camera body would depress a pin that would release the lens and allow it to be removed, if the lens release button was simultaneously pushed and the camera was in manual focus mode. This did not work either.

  163. 163
    Molly randolph:

    Thanks so much! Thought I was stupid. You have shown me that using the old lenses is really more trouble than I want, and I am happy with the new. Save me a lot of time.

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