So normally I use the 180mm Sekor C and do portraits for quite some time, haven't shot landscapes in ages.

I own the 50 C with floating element, 90 C and 180 C.

I decide I would test the lenses and check everything out.

I decided I would photograph a test chart about 10m away.

The 50mm couldn't focus that far away, it looked, it is not the viewfinder/screen/etc (using WLF), as the bellows were racked all the way back and can't go back any further. The focus in the image (Developed neg) looks at about 3m at the infinite focus setting. In the viewfinder I think it did look further down, very close to my subject, but just shy of it -I think-.

The 90mm looked a lot better, but also focused it at minimum bellows (couldn't go back any further again). The test chart is outside the DoF, so it's out of focus, but maybe by about a metre or less?

My focus with the 180mm was -just- off, I did have to use a very small amount of bellows extension to focus it, so that seems normal. And the focus error may simply be my error.

Now I don't think it's the mirror/screen/viewfinder etc being out, because being racked to infinite with my object at ~10m, but having focus closer than that indicates the lens needs to be closer to the film.

I don't think it's the back because I saw I couldn't quite focus properly in the viewfinder.

Now I don't think all the lenses (or at least the 50 and 90) are both somehow out (moved elements somewhere?) as that seems very unlikely.

But there is nothing obscuring the bellows from closing to minimum extension, and it sits flush at the bottom where it touches the camera body when closed, so I dont think its possible for the bellows aren't being drawn all the way in.

I think the lens mount itself is protuding/extended as that doesn't look possible for it to happen.

When I mount the lenses they are secure and there is no play at all.

Any suggestions? Kind of puzzled.

Body is ProS not ProSD, lenses are Sekor C's, backs are Pro backs, (ProS back bunged out on me a while back)

Given the fact it didnt seem to focus pin sharp in the VF, close but not quite, but that I think its focused closer than it is in the viewfinder, I think both the lens is not sitting close enough in somehow, and the film is also too far out.

Now the back I used put some foam seals in it myself (inc the revolving back). I didn't do the best job, but it seemed to be fine at the time, so I'm wondering if I'm pushing the back or part of the back out a little to throw the film plane off (as well as the lenses/mount being out somehow)

I'll attach some pics of that.