Old screw mounts from the early 80s on a K20D

[LordJezo]

Hello.

Just came across this website when searching for an answer to my question.

We have an older SLR Pentax camera from around 1980, it uses Pentax's old style of lenses, the screw mount types. I have seen other people ask similar questions but I dont know if they were about these lenses that are almost 30 years old.

They are all in great working condition, it's just that Pentax switched their mount styles to the bayonet types a while ago and I don't know what the new DSLRs use.

Can we take lenses this old with some sort of adapter and use them on new digital cameras? I see that the K20D has image stabilization built in to the camera itself, not on the lens, so does that mean that even with these old lenses we could use the feature if it's possible to mount them?

[emr]

If it's the M42 thread, yes you can use them on your K20D with a suitable adapter. And the original Pentax adapter is the recommended one.

But you'll find tons of info with search on this forum.

Originally Posted by LordJezo

I see that the K20D has image stabilization built in to the camera itself, not on the lens, so does that mean that even with these old lenses we could use the feature if it's possible to mount them?

Yes.

[Mike Cash]

Absolutely you can use the lenses; you just need a simple little adapter that costs about $30.

The lenses are over thirty years old, by the way. The switch from screwmount to bayonet mount happened somewhere around 1974.

You may wish to visit The Takumar Club thread, which is the longest single thread on Pentax Forums. Plenty of images from those old lenses there, so you can get some idea of their performance on modern digital bodies.

[monochrome]

WELCOME! Many of our members have screwmount cameras and lenses and use the lenses on our K-mount cameras, as well. We are here to help, so keep asking questions.

Here is a link to the Mount Adapter K at the Pentax Webstore. This adapter allows you to mount M42 screwmount lenses to K mount bodies such as the DSLR's, as you asked. Since your lenses have screw threads on the mount end and (probably) have "Takumar" printed on the front ring, you will need this adapter to mount the lens to a modern camera. Fortunately, once mounted with the adapter, you can use these lenses with some limitations and extra steps with virtually any Pentax camera body made.

If you want to do a bit of research on your camera and lenses - perhaps place them in history - please visit the Asahi Optical Historical Club website and Paul Provencher's excellent Asahi Pentax website dedicated to screwmount cameras and lenses.

If you are interested in the "new" bayonet mount cameras and the history of and technical data on the K-Mount, visit Bojidar Dimitrov's K-Mount Page, an incredibly complete and up-to-date website on virtually EVERY item made by Pentax since introduction of the K "Bayonet" Mount.

That ought to hold you for a year or two - Have Fun!

[pschlute]

I use a few Takumar M42 mount lenses on my K10. A joy to use these old lenses. You also have the advantage of being able to use Av mode with these lenses, unlike the manual "K" and M bayonet mount lenses that followed.

One disadvantage is that as you stop-down, the viewfinder gets darker, so my advice is to focus wide open, then stop down to your desired aperture.

And make sure you get the genuine Pentax adapter. Some of the generic ones do not allow the lens to sit correctly and you lose infinity focus.

The way to use the adapter is to screw it onto the lens then bayonet it onto the camera. To remove the lens you need first to unscrew the lens, then remove the adapter.

[Mike Cash]

Originally Posted by pschlute

The way to use the adapter is to screw it onto the lens then bayonet it onto the camera.

Or, as Pentax recommends, mount the adapter to the camera and then screw the lens onto the camera body. Six of one and half a dozen of the other, though.