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09-16-2011, 02:36 PM   #1
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SuperProgram backfocus

I found that my SuperProgram is backfocusing. I focus carefully using the split screen and get images where backgroud is in focus and subjec out of focus. I can remove the focusing screen and try to shift it but which way? And how to ensure the next film I expose will be in focus again?
Any advice is much appreciated.

09-16-2011, 02:57 PM   #2
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Where did the Super Program come from? Had the camera been serviced recently?
09-16-2011, 03:36 PM   #3
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I bought it second hand, sometimes last year. It seemed to be in perfect condition. I do not shoot film a lot, but after second roll of badly focused pictures I started to suspect something.
I do know how to focus properly, I never had such problem With OM-G, Praktica or Ricoh XR7.
09-16-2011, 04:18 PM - 1 Like   #4
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Not knowing in person the camera, I'll just say that a few possible things might be wrong.
If service by a person who was less than careful, then the possibility of missing shims in the face plate has rendered the focus off, or that the person did not reset the focus after cleaning the screen. Well, here, have a look...



circled is items M28 the illustrated set screws.

In some cameras, the layer of foam dries out and can change the focus.

09-16-2011, 08:19 PM - 1 Like   #5
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Mirror out of alignment? That and improper shimming of the focus screen are the are the only places where things can be out of adjustment. There is one other, that we really don't want to consider. That being that the camera had been dropped with a resulting bent/broken chassis.

You can check the focus by putting the camera on a tripod with the back off and taping a piece of groundglass or a junk focus screen over the shutter opening at the film plane. Focus with the viewfinder and then open the shutter (B setting with cable release) to check the focus on the ground glass.


Steve


(One other possibility is focus shift on stop down...though such is fairly unlikely.)
09-17-2011, 01:45 AM   #6
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Thank you very much. I'll see where I can find the groudglass and a screwdriver small enough and try to adjust it.
09-17-2011, 03:18 AM - 3 Likes   #7
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It's pretty easy to adjust focusing on Super Program. Just mount a 50mm lens (or any lens similar), turn the lens focus ring to infinity, and point at a straight line (eg. a far away building). If the split images don't aline properly, the focusing is out. You can then use a small screw driver to turn the three screws (you can see them when you take off the lens and looking at the front/left/right rims of the screen, they are the M2B screw in the above photo posted by MysteryOnion) on the front/left/right of the screen left or right to adjust the focus. To be safe, try to adjust the front screw first. If still can't make the focusing right, you can turn the left/right screws, but make sure you turn the same amount (so to avoid tilted screen).

I've done this on at least two of my Super Program, pretty straight forward

Good luck.
09-17-2011, 09:35 AM   #8
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QuoteOriginally posted by frank Quote
It's pretty easy to adjust focusing on Super Program. Just mount a 50mm lens (or any lens similar), turn the lens focus ring to infinity, and point at a straight line (eg. a far away building). If the split images don't aline properly, the focusing is out. You can then use a small screw driver to turn the three screws (you can see them when you take off the lens and looking at the front/left/right rims of the screen, they are the M2B screw in the above photo posted by MysteryOnion) on the front/left/right of the screen left or right to adjust the focus. To be safe, try to adjust the front screw first. If still can't make the focusing right, you can turn the left/right screws, but make sure you turn the same amount (so to avoid tilted screen).

I've done this on at least two of my Super Program, pretty straight forward

Good luck.
Wow! The members of this forum never cease to impress me! I own the Super Program, but was unaware that the focus screen adjustment was this easy. Thanks for sharing this tip!!


Steve

09-17-2011, 11:30 AM   #9
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There is a good chance the copper washers sandwiched between the mirror box assembly and the chassis are left out after service. This is rather common with Pentax manual focus bodies. Since the film plane distance will be shorter, it BF and the lens distance scales aren't accurate anymore.

Turning the 3 screws (M28) on the focusing screen metal frame is easy enough, but getting all 4 corners to match the actual film plane is next to impossible w/o the proper instrument. Also, those screws are threadlocked from the factory and must be threadlocked again after repair. Since new screen can't be obtained, be extra careful toying with the screws. If possible, has it done by the pro.
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