Problems concerning film flatness

As you may see on the picture, the upper and lower film edges tend to curling.

If the upper and lower edges of the film are pressed down, how will the center area react? The center will come up. This is the actual situation in Pentacon Six cameras:

The weakness of the original pressure plate of Pentacon Six adds to this effect - the plate itself bends towards the lens in its center. A laid on ruler makes this visible:

An easy solution is giving the plate some bend in the opposite direction in order hat the plate will lie flat under spring tension with the camera back closed. This „Economy“ solution is part of CLA at baierfoto. It works well with film type 120. Swapping between 120 and 220 type is not recommendable – but possible with an intermediate adjustment of focus.

Most customers have been preferring this solution. The former baierfoto Premium version is no longer on offer. Production costs were increasing while demand was low.

Flatness with Kiev 60 and Exakta 66