[educorgan]

Hi everyone.

I actually have a Helios 44M-4 58mm f2 lens with a M42 mount that I really loved to use on my dad's old Zenit film camera. I got a M42 > K-mount adapter on Ebay and I can in fact attach the lens to my Pentax K-3 now but it doesn't seem to work properly. I cannot focus. Whether I'm trying to focus on distant objects or near objects, it seems as if I needed to still turn the focus ring on the lens more to be able to focus but it doesn't move any further. I hope I was able to explain myself properly.

Is this a known issue? Is there any way to solve this?

Thanks in advance!

[UncleVanya]

Which model Zenit? Is the lens fully screwed in? Does the M42-to-K adapter have a flange on it that sits in front of the K-mount or does it go all the way inside of it like the official Pentax one? Can you provide a photo of the Pentax camera with the adapter and lens?

[JohnX]

Some non-Pentax M42 adapters will not allow infinity focus.

[jlstrawman]

How to use/meter Manual & M42 Lenses on all Pentax DSLRs (K-1, K-3, K-5, K-30, etc) - PentaxForums.com

Check out the above article and make sure Using Aperture Ring" custom function is set to "2 (allowed)

[Skodadriver]

I have the Helios-44-M-4 and have no trouble focussing it on my K-5 with either a Pentax original adapter or a flanged adapter (that loses infinity focus).
Did you fix the aperture pin to enable changing the aperture with the aperture ring or do you have an adapter that depresses the pin automatically?
If you dissembled the mount to fix the pin you may have disturbed a lens element.
Sorry no help here, maybe someone else will recognise your problem.