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08-13-2009, 03:07 AM   #1
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M42 12 blades mystery lens need Help

Just got this lens, cosmetically looks like new but I can not get any focus right, the smallest focus distance supposed to be 0.9 of a meter and I can not get any focus even 20 meters away.
The lens in question is a .. ( Phot-All 35mm f/3.5 ) made in Japan, this lens has pre set aperture and wait!!! 12 aperture blades.
There is no fungus in it, the optics are in great condition, some signs of a little oil or some insignificant small marks on aperture blades.
I’m extremely interested with fixing this lens because of the amazing bouquet that I suspect this lens can produce. I suspect that this lens was perhaps disassembled and put together the wrong way.
I wonder if any one has come across this lens or knows of a site where I could find some information on how to repair this “little mystery”.
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08-13-2009, 04:13 AM   #2
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I think I have the f/2.8 version of your lens. I really think is by the same maker based on the layout and lettering, and even the order of the information on the beauty front ring and the numbering seems also close.





The manufacturer is still unknown to me. Kashimura is (was?) a Japanese exporter of optical goods. Kashimura - Camerapedia.org
08-13-2009, 04:31 PM   #3
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This may be just a silly thought but does it have a filter on it? If so, try it without the filter.
08-13-2009, 07:29 PM   #4
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Thanks Asahiflex for taking the time to reply. Your lens looks definitely similar, almost exactly the same as mine.
Nice to know that my sick lens has a cousin in Europe.
Now if we could just find out who the makers are then maybe I can chase some repair manual or some kind of diagram how those lenses are built (put together).
Somehow I feel that I could get great results from this old glass, but first I have to fix this problem with focus or rather the lack of it.
Wonder what your experience with your lens is.
Can’t really compare exactly both of them because yours is f/2.8 to mine f/3.5 but still they are share same build and most probably by the same maker (and those beautiful little 12 aperture blades  ) .
Maybe someone up there has some instruction how to open lenses with pre set aperture and knows all the tricks with those kind of lenses.?????
I will keep trying.

08-13-2009, 07:34 PM   #5
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Thanks Damn Brit for taking the time to reply. From the side it does look like there is a filter screw on but there is none.
The best way to explain this problem is that all my lenses work ok with split focusing screen, but this one you simply can not get to focus so that the split screen will align itself.
The shortest distance (according to what is said on the lens) supposed be 0.9 meter, and even standing 10-15 still can’t align split screen.
I suspected that this lens was disassembled before and there must be some glass put together in the wrong way or is not aligned properly.
I will try to find some instruction on how to open lenses with pre set aperture, if I can’t then I will go ahead and I try my luck finding whats wrong with it.
08-13-2009, 09:16 PM   #6
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Is it possible this lens isn't made for the M42/K-mount cameras?

The lens flange-to-sensor registery distance for Pentax mounts is 45.46mm. Even a few mm's difference causes significant shift in focus -- as with extention rings.

Hold the lens upright under a light bulb over a white surface. If it focuses the image of the bulb filiment sharply the lens is probably OK. If it doesn't focus sharply at 45.5mm it's not a Pentax mount lens or has been miss assembled.

Google - lens registry distance - for more info. A comprehensive table of lenses is at:

Camera Mounts Sorted by Register

(This would be a useful sticky too.)

H2
08-13-2009, 11:43 PM   #7
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Hi Paccer and thanks for all the info!!!!
I did check the lens flange-to-sensor registry distance without M42 adapter (which of course I have one - Pentax original) and compared to my sharpest M42 Fujinon EBC 50mm f/1.4 and is spot-on.
I didn’t have any clear bulb so I checked on the text written on the card with a distance of 45.5mm.
Both lenses were spot-on with sharpness. What now????? 
08-14-2009, 01:35 AM   #8
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How about another test. Take the adapter off your camera and screw one of your good lenses into it, see how far it screws in and maybe mark on the adapter where it stops.
Do the same with this non focusing lens to see if it screws in to the same point.
Just an idea and call me Gary by the way.

Alternatively, attach the lens to the camera and then unscrew it slightly to see if you can find a focus.


Last edited by Damn Brit; 08-14-2009 at 01:57 AM.
08-14-2009, 03:29 AM   #9
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Thanks Gary.
I did what you have suggested and the adaptor screws to both of the lenses all the way to the flange, sitting nice and flat, with the same amount of turns, so that only confirmed that the distance, from the flange to the sensor, with or without adaptor, is the same on both lenses.
It really got me stuck, maybe I will dismantle this thing but first I will try to get some diagrams and try to understand how this works, or even better, a repair manual.
What got me stuck was the test which was suggested by pacerr

"flange-to-sensor registery distance"

on this lens and 5 others proved it was spot on.
08-14-2009, 04:14 AM   #10
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It's entirely possible that somebody at some point disassembled it and put it together not paying attention to the helical threads. That would massively throw off focusing.
08-14-2009, 05:10 AM   #11
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Thanks for this contribution Pingflood
If that is the case I will definitely need some kind of diagram or repair manual for those kind of lenses (pre-set) as I have never opened one of them and I’m not really sure how to properly take care of (align?) helical threads. :-(
08-14-2009, 05:50 AM   #12
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Well, if the helical's off, the only thing I know to do is trial and error. You might want to visit the classic camera forum (don't have the link handy) where some repair guys hang out.
08-14-2009, 05:53 AM   #13
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By the way, have you discovered already that the back part of the lens can be screwed off? This is because you have a T-mount lens; the T-mount is also of a 42mm thread but different. Make sure you have the right mount.

Also... is focus always impossible, even in the macro range?
08-14-2009, 12:14 PM   #14
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You can always e-mail them and ask.

Kashimura Co. Ltd.: Private Company Information - BusinessWeek
08-14-2009, 12:33 PM   #15
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Pentax 50mm f/1.4 strip-down instructions

Google - lens repair - and similar. There's illustrated lens dissassembly instructions which will either get you started or convince you to write it off.

Unless you've indexed a lens before you take it apart, finding the correct focus combination's pretty much trial-and-error -- mostly error, in my case. In your situation, index the present, non-working arrangement before you take it apart so you don't duplicate it. Be prepared to pay your dues!

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