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Help With Alpa Schneider 35mm APO Digitar Focus Ring

rga

Member
Sure would appreciate any advice. The infinity mark on my Alpa 35 now moves way past the distance mark (to the left of the distance mark if looking from the back of the camera) almost to the left f/8. Per the GG and images, infinity is still on the mark (though, I haven't really been able to test it...).

Any advice would be greatly appreciated.
Thanks,
Bob
 

PeterL

Member
There is enough curvature of field with the 35XL that the center and edges have slightly different focus. The actual infinity marker is set for the center of the lens and the actual stop is for the edge of the lens. In practice, it works very well to set the lens at the marked infinity and then stop to f/8 or so to ensure that the edge of the field is also sharp. This is the explanation Paul Slotboom gave me a while back.

Cheers, -Peter
 

rga

Member
There is enough curvature of field with the 35XL that the center and edges have slightly different focus. The actual infinity marker is set for the center of the lens and the actual stop is for the edge of the lens. In practice, it works very well to set the lens at the marked infinity and then stop to f/8 or so to ensure that the edge of the field is also sharp. This is the explanation Paul Slotboom gave me a while back.

Cheers, -Peter
There are three small Phillips screws on the focus ring. They may have come loose.
Thanks both. I'll take a look and test today. Other ideas also welcome,
Bob
 
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