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05-29-2012, 09:57 AM   #16
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Drum roll ... please

Bonjour et tah-dah !

I modified the CZJ just like a Yashica and it worked ... still testing, but all looks quite promising!

Here's the end result below ....

Salut, John le Frog









05-29-2012, 10:49 AM   #17
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You dremeled the Praktica bayonet mount to fit PK body? What about the difference in the register distance, if you haven't done anything to that then you won't have infinity focus. Here is a chart showing the register distance of various cameras manufactured: Camera Mounts Sorted by Register You will need to remove 1.06mm from the barrel of the lens to get infinity focus but if you don't care about having infinity focus (may not be much of a factor since the lens can be used within almost all focal length range, just shy of infinity).
05-29-2012, 11:02 AM   #18
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My reaction is the same as @excanonfd. That registry difference may limit far-focus to maybe ~3-9m depending on f-stop. Nothing wrong with that, we can always use specialized lenses with limitations that challenge our creativity. I have a few fixed-focus lenses that keep me challenged. I may end up accepting the same limit with my Prakticar 50/2.4 copy.

Meanwhile, I must get off my lazy butt and finish a mod of a Petri CC 35/2.8. The trick with it is to establish aperture control. I just need to jam *one* piece into place... but that piece is in an almost unreachable position. Once that's in place, I'll just glue-on an M42-PK adapter, and wail! Oh yeah, and I must post a thread on my lens mods and adaptations, with pictures. [/me sweats already]

Last edited by RioRico; 05-29-2012 at 11:11 AM.
05-29-2012, 11:37 AM   #19
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Merci ...

QuoteOriginally posted by excanonfd Quote
You dremeled the Praktica bayonet mount to fit PK body? What about the difference in the register distance, if you haven't done anything to that then you won't have infinity focus. Here is a chart showing the register distance of various cameras manufactured: Camera Mounts Sorted by Register You will need to remove 1.06mm from the barrel of the lens to get infinity focus but if you don't care about having infinity focus (may not be much of a factor since the lens can be used within almost all focal length range, just shy of infinity).
Bonjour excanonfd,

Thanks, but I knew that infinity would be lost ... a sacrifice that I accepted considering what I want to do with this lens ...

There's no way that I could machine due to skill, time, etc. ... plus I do not even see how that could be done at all without ruining all of the lens ...

Salut, John

05-29-2012, 11:45 AM   #20
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QuoteOriginally posted by RioRico Quote
My reaction is the same as @excanonfd. That registry difference may limit far-focus to maybe ~3-9m depending on f-stop. Nothing wrong with that, we can always use specialized lenses with limitations that challenge our creativity. I have a few fixed-focus lenses that keep me challenged. I may end up accepting the same limit with my Prakticar 50/2.4 copy.

Meanwhile, I must get off my lazy butt and finish a mod of a Petri CC 35/2.8. The trick with it is to establish aperture control. I just need to jam *one* piece into place... but that piece is in an almost unreachable position. Once that's in place, I'll just glue-on an M42-PK adapter, and wail! Oh yeah, and I must post a thread on my lens mods and adaptations, with pictures. [/me sweats already]
Bonjour Herrn Doctor RioRico,

Thanks (as always) for your input and far-focus seems to be at 3 to 4m range, but haven't test shot too much here ... Close-focus and kids' portraits are the main goal for me with this one.

Please do thread/post photos of your mods, etc. Maybe we could go "quadraphinic" and start a Mod's Frankenlens Club ... Who? Who would join ...

Salut, "Eyegore" - AKA John

Last edited by Jean Poitiers; 05-29-2012 at 12:51 PM.
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