[Robert S Donovan]

I'm sure this has been covered many times before but I thought I'd take my own stab at it on my blog. Hopefully this will help all those people who mount up their first M series lens and encounter the dreaded flashing F--

Shooting manual lenses on Pentax DSLRs

I'm no expert on manual lenses so I'm sure you guys will let me know what I missed

Cheers!

Admin edit to sticky - you may also be interested in reading this article: https://www.pentaxforums.com/forums/pentax-dslr-camera-articles/100260-manual...ic-lenses.html

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Last edited by Damn Brit; 05-05-2009 at 11:57 AM. Reason: Added to title.

Good idea Robert and thank you, I think it'll be better in the beginners section, I'll sticky it. Can you also submit them to the articles section please?

Let's hope members send people to this thread when the question is asked, instead of answering it over and over again.

[Marc Sabatella]

Wow, that's really a ncie looking article! I skimmed through it and it looks well-written too - and I love the cracked LCD cover in the illustrations :-)

A coupe of minor observations:

"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."

Took me quite a whiel to parse this. At first, I thought the subject was "series K mount lenses", and I wonder why you would use the indefinite article "A" since the subejct was plural. Then I realize you must have meant "A series" lenses. I'd suggest either putting the "A" in quotes, or eliminating the phrase "K mount", or putting the word "The" in front of the whole shebang. Actually, though, I'm not sure the sentence really says much - *of course* they are manual focus lenses. So are the M's, and also the M42's. Maybe you meant to emphasize that focus is the *only* thing manual about them?

Overall, I'd consider putting the M stuff before the A stuff, because way more people have M than A, and it might take them a while to wade through to find the stuff about the aperture ring. Or maybe put a link toward the top to let them jump right to where they need to be.

You should mention difference in models as far as what have what type of button to press to set the exposure (*ist D, K10D, K20D, K200D = green; *ist DS, *ist DL, K100D, K110D = AE-L, K-m/K2000 = "+/-", I believe). Also, be aware that the meter display you get via DOF Preview is only a bar graph on the K10 & K20D - it's numeric only on all other models as far as I know. And the K-m/K2000 lacks the DOF Preview entirely.

Sean Nelson, as you may know, wrote what has been the definitive guide thus far, in a thread on dpreview:

K100D (Super) Pictorial guide to using manual lenses [imgs]: Pentax SLR Talk Forum: Digital Photography Review

His has a certain step-by-step simplicity worth looking at, and if nothing else, providing a link to.

[Robert S Donovan]

Thanks, Marc. I totally agree with your whole "A series" confusion thing and added quotes to the "A". You are probably correct about most people shooting M series lenses. I purposefully put the "A" series instructions first because most of the blog posts I found when trying to figure out how to use my A series lens dealt with M series lenses. Most of the stuff I cover w/r/t setting the focal length, focusing and exposure are applicable to M series lenses as well as A series lenses.

Unfortunately, I only have direct experience with my K10D so I don't feel comfortable talking about other models. I would like to add instructions for other cameras to make this a true Pentax DSLR manual lens how-to. If members here can provide model specific input I will update my original blog post accordingly.

[Marc Sabatella]

The only models I'm not sure about in my quick charaterizations are the *ist D and K-m/K2000. I'm pretty sure the D has the Green button and DOF preview, but not sure if it does the bar graph or not. And while I know the K-m does not do DOF preview, and the "+/-" ends up being the button to use to set exposure, I am not sure if there is a specific series of steps needed to customize the camera in order to get that far, nor am I sure if has a bar graph or not.

[Robert S Donovan]

Me neither ;-)

[res3567]

The only models I'm not sure about in my quick charaterizations are the *ist D and K-m/K2000. I'm pretty sure the D has the Green button and DOF preview, but not sure if it does the bar graph or not. And while I know the K-m does not do DOF preview, and the "+/-" ends up being the button to use to set exposure, I am not sure if there is a specific series of steps needed to customize the camera in order to get that far, nor am I sure if has a bar graph or not.

Yes. The original *istD does have a green button.

Why did Pentax give that camera series (film and digital) such a funky name?

[iht]

I'm sorry in advance for what might be a dumb question, but then again this is the beginner's section!

I read an article on dpreview on the subject of using M42 lenses. It mentions the following re hitting the AE-L button when metering:

When you hit the button the camera will momentarily stop down the lens to take a light reading, then it will set the shutter speed to the appropriate exposure. You'll see the new shutter speed in the green digits below the viewfinder image. After setting the shutter speed the lens will immediately open back up again - the whole thing takes about a second.

My question is: how does the camera "tell" a completely manual lens to stop down to the aperture set by the aperture ring? Is this via some mechanical process, or is it by sending the lens some sort of electrical signal?

I'm still a bit confused about the function of the green button and the AE-L button re metering on a M42 manual lens.

Btw, our family owns a Super Takumar f1.4 50mm lens, so this is the lens I'll be working with once I get a K20D.

Thanks in advance.

[Marc Sabatella]

The instructions you are quoting from invovle K-mount lenses, not M42 - the process is different for M42. However, to answer the basic question, with K-mount lenses, it is a mechanical process - there is a little lever sticking out the back of a K-mount lens, and the camera pushes that lever to tell the lens to stop down. You can do the same with the lens sitting in your hand to get a feel for how it works. But again, M42 is different, and I know there are at least 2 or 3 different types of M42 lenses as far as aperture goes.

[ancatdubh]

Robert, thanks for the blog post - it very nearly got me to the end point of a question that is presently on my mind.

I would be much obliged if anyone could clarify the following for me;

If I want to use SR (shake reduction) with a manual lens (the 50mm f1.7) does crop factor come into it at all? i.e. should I be selecting a 75mm lens setting when I turn on the K20D for the shake reduction to work at its best?

Cheers.

[Marc Sabatella]

Focal length is focal length. The "crop factor" doesn't change it. If you mount a 50mm lens, enter 50mm as the focal length, because the focal length *is* 50mm. Your camera doesn't care what kind of view the lens might have provided on some other camera.

[ancatdubh]

Thanks a million Marc - that should give me a little piece of mind this coming weekend.

[Big Bob]

Need some help with an M42 55mm f1.8 on K100D. I have been successful in using the lens and getting the meter to operate. What I am having a problem with is SR. I do not get prompted for focal length and the SR item on the menu is grayed. Also, LCD info says SR is not on even though switch is on. Should I be able to use SR? What am I missing. Thanks in advance for your help.

[Daveinozbikes]

Need some help with an M42 55mm f1.8 on K100D. I have been successful in using the lens and getting the meter to operate. What I am having a problem with is SR. I do not get prompted for focal length and the SR item on the menu is grayed. Also, LCD info says SR is not on even though switch is on. Should I be able to use SR? What am I missing. Thanks in advance for your help.

Big Bob...I have one of the same lens and a K200d.. The reason you are having this problem is the camera does not recognise the lens. The M42 thread on the lens is plastic and very narrow. It does not contact the little "pins" on the camera bayonet
I altered mine to a permanent bayonet instead of M42 and it took me ages to discover these facts. Also because of this you cannot use "catch-in focus".... there was much scratching of head ....

You can overcome this by putting a wide adapter on the m42 thread but you lose infinity focus. I used the narrow adapter which does not contact the pins but alows infinity focus. Horses for Courses eh?? To get metering just wind EV up using the av button and wheel.It takes a beautiful image.

[bluesky123]

Is there a "reverse" tutorial--how (if this is possible at all) to use Pentax DA lenses with older film cameras?

My daughter is going to take photography class in college and, for some classes, they require film cameras. Having K10D (my daughter and I love it!) with Pentax DA 50-200mm and Sigma 17-70mm DC macro Lens
Amazon.com: Sigma 17-70mm f/2.8-4.5 DC IF Macro Lens for Pentax and Samsung Digital SLR Cameras: Camera & Photo
I hoped to buy just a body of a film Pentax SLR to use it with one of these lenses. I was thinking of Pentax ZX-60.
Is it possible? Or I need a different film camera, which one?

Thank you,
Boris