Konica III pressure plate question

I have this Konica III:

 

http://i8.photobucket.com/albums/a11/julio1fer/Konica%20III/IMG_0874_zpsf0b521de.jpg

 

The pressure plate in this camera has a horizontal play (in the direction of film movement) of a few mm. The plate is firmly held by its springs and seems to cover the film gate in every position of its short trajectory. It does not feel as if something is loose. There is no vertical movement, just horizontal translation.

 

¿Any other Konica III owner out there? I would like to confirm if this is a camera feature or something I should have repaired.

 

The camera has given good service, but in a few frames I have noticed lack of sharpness on a side, which may or may not be caused by the pressure plate.

 

Thanks for any comment!

Julio,

 

I don't have your camera, but from photos I've seen the pressure plate has cutouts on the corners. I have a FED camera that has a T-shaped pressure plate (cutout on one side to fit between the sprockets). I also noticed some slight image softness on one side, corresponding to the same side as the cutout. When I looked at the pressure plate I noticed it was not quite level, so I adjusted the springs and it seems to have helped some. Perhaps if there is enough lateral movement, the film could curl up a bit where these cutouts are.

 

I'm not sure if what you are seeing could be caused by a loose lens element--sometimes retaining rings can work loose.

 

Dave

Julia Fernandez said:

The pressure plate in this camera has a horizontal play (in the direction of film movement) of a few mm.

 

I had a look at a somewhat similar S2 and that also has a pressure plate which is free to move about 3mm to and fro horizontally. The plate held in position by four flat spring steel arms attached to the back, and studs on the rear of the pressure plate house into slots on the end of the arms.There is no hard fixture between the plate and the arms.

Edited January 20, 2019 by rick_drawbridge

Thanks for the comments! Dave, I was suspecting a curling problem, that is why I checked the plate. The lens seems fine and actually most of the pictures have been sharp.

 

The pressure plate is held by four spring arms attached to the back, similar to what Rick describes for the S2. The plate seems attached by rivets that go through the back of the pressure plate into slots in the spring arms. Knowing that the S2 also has some sliding horizontal play is reassuring; it seems a normal feature. Horizontal sliding movement is about 2 mm in my Konica III. I believe that the springs actually need to slide when the plate is pressured, therefore this sliding play.

 

I have now figured out the position where the plate should be in its slide, such that it centers on the film gate, I have also verified that the plate does not move by friction when winding a 15-frame discarded film. Next test roll will tell what happens!

To complete the thread: Thanks to a friendly message from another Konica III owner (the great MIke Elek), I got enough courage to press harder those springs and take out the pressure plate (I had never taken out a pressure plate before, excuse my inexperience!).

 

It is held by slots, not riveted as I had thought:

 

http://i8.photobucket.com/albums/a11/julio1fer/Konica%20III/Konica%20III%20pressure%20plate-s_zpsdgj2vyl8.jpg

 

Those slots are long enough to allow movement, so it becomes a feature and not a bug. Thanks again for the answers, and excuses for a trivial question.

Thanks for sharing, Julio. I think the slotted fittings are pretty typical, though most cameras I've seen have the springs attached to the back of the pressure plate and not the door. Hope to see some of your test photos!