Pentax K lens on Leica M body

Because I hate lens slap and enjoy taking exposures in low light/ low shutter speed.

One of the best low light cameras ever made was the Fujica ST 901. Bright viewfinder, SBC metering (EV -3 to 18) so 20 seconds to 1/1000 with ASA 25 film, shutter speeds in the viewfinder (speeds, not led next to unreadable numbers), small, uses all M42 lenses with automatic exposure (only open aperture with Fujinon lenses), easier to focus in low light that a camera should be as it has RF as well as a bright screen. I have used one about 35 years and it still works fine.

There may be others, but I don't think any match the ST 901. I have yet to try my Contax 167mt, but don't think it will be quite as handy.
 
You probably could find someone to build some type of adapter that would allow you to use an SLR lens on a rangefinder body with RF coupling. However, you'd probably need a different adapter for each lens, and the fact that they're "one offs" means they would be very expensive.

I think you should get someone to build one and see how things work out.

By the way, what is "lens slap"?
 
on left: 43mm 1.9 cop.
on right: uncropped other image
I compared this lens with the Summicron-C.
Both looked very good.
 

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The 43 in LTM is a very nice lens- crisp, with nice bokeh. This has me thinking of putting an old Pentax 35 in that other thread mount on an M...
 
Transferring the movement from a Pentax M42 50mm f/1.4 SMC Takumar should be just an exercise in fabbing up a way to get the RF to couple.
Usually, this is the hardest part of getting other lenses to work on RF cameras but in the case of this particular lens, the total movement from infinity to close focus range (of an M camera) is within .02mm of the motion of a DR Summicron. I've measured it a bunch of times and came up with the same result.
Over the last few years I've tried to come up with a way to transfer the motion of the lens to the RF cam-follower in the M body and using scavenged parts from third party lenses seems the best route.

The LTM 10.5cm Nikkor lens has an intermediate cam-follower between the lens cam surface and the Leica cam-follower. This is a unit piece which is sufficiently long enough to bridge the gap between the rear element of the Takumar and the Leica cam-follower. The only thing I need now is a sacrificial 10.5cm Nikkor (I shudder to think of this) and I'm in business with a rare-earth 50mm SMC Tak on my Leica M WITH RF coupling.

Phil Forrest
 
Wow Phil, you grasp this concept a lot better than I do. If you ever figure it out, I would be happily to pay you to convert mine. Think it's a possibility?
 
It's absolutely a possibility. It wouldn't even be a conversion, just an adapter that you would screw the SMC Takumar 50/1.4 onto then mount to the Leica M. The problem is getting the sacrificial lens. I suppose that someone with a CNC machine could make the part I'm thinking of using as the intermediate cam-follower but I don't have access to anything like that, nor do I have the funds to hire someone to do experimentation.
I guess I could design it in Autocad then send off the blueprint to have it fabbed up. Regardless, it would be an expensive adapter at first.

Phil Forrest
 
I've done it with a Leica SM to Pentax M42-Pentax made adapter and then added to that a number one extension tube. This gave the correct distance away from the film plane. I have only used my Pentax super takumar 28. It is zone focus only. The only problem is a finder. I have a 35 finder that I use but I would like a 28.

I'm going to check with Novaflex for screw to K mount so I can use my 20mm K.
 
The early Pentax lenses are excellent even today. I use Pentax screw mount lenses when I can but as stated elsewhere in this thread, adapters do not couple to the rangefinder so you are stuck with zone focussing using wide angle lenses basically.

More recently I have bought a Sony NEX camera. The adapters for Pentax - NEX can be found cheaply (most $20 adapters seem to work fine even though you cna pay ten times this amount for a novoflex one) and they produce nice results on this system. I find it more satisfying than using them on my M system as I can use fast primes like the 85mm f1.8 and focus accurately wide open.

But as I said I mainly use screw mount not K mount lenses. The only slight weaknesss in these cameras are that their coatings are not so good as found on cameras today (although the SMC coatings are better) and early Pentax glass does not quite have the flatness of field of Leica M glass - so perform slightly less well in the outer part of the image - although they tend to perform extremely well in the image centre.

BTW one of the nicest performing lenses as far as good sharpness and excellent bokeh goes is the 50mm f2 (or f1.8). It is dirt cheap, usually costing under $50 on Ebay.
 
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