Focus Issue around edges

[Tobias Key]

The only time I have seen something like that is when I took the whole rear cell off the back of my 360mm tele-xenar. It looks like a major lens issue. Like others have said it could be there is a washer/spacer missing, maybe someone has combined cells from two different lenses for some reason. It really needs to be in the hands of someone skilled in lens repair or you need to compare it to another example of the same lens, unless of course it is simply badly assembled in some obvious way.

[ic-racer]

Are you sure you remembered to stop down or the aperture mechanism is not working. Posting a picture of the negative is always helpful.

[Alex DiBacco]

+1
Do you check if the lens originally has some washers between cell/shutter, and maybe missed?. Or the opposite scenario?
Is the shutter(aperture diaphragm) working properly? I mean during exposure?
Is it assembled on the correct shutter?
Scanned photos still may corrected before downloading.
Good luck Alex.

Thanks Doremus and Thalmees. I have shot good images with this lens only when stopped all the way to f/64 and with movements. It's fine for still life because I can take long exposures to work with the small aperture, but I've never been able to get it it completely sharp across the whole image.

The lens I purchased used ($800 for the camera, lens, and 2 holders, seemed like a great deal). Iris looks and behaves fine, and the shutter speeds seem to be pretty spot on. Nothing on the lens feels like it's loose. There are some scratches/dings on the backside, possibly from the rear element housing getting continuously bumped when removing the lens.

It's more than likely the problem is stemming from either being banged by the previous owner or an incorrect reassembly. I don't feel comfortable taking it apart myself, so I will just have to send it in somewhere to get repaired.

[Thalmees]

... I don't feel comfortable taking it apart myself, so I will just have to send it in somewhere to get repaired.

Hello Alex,
I do not think so, at least at this time. Sorry for this expression.
When you would like to swap lens boards, you should take lens cells from shutter or at least the rear cell, to access the flange ring. It's just counterclockwise disassemble.
But, please watch any spacers, they could be located:
1. Between, the rear element of the front cell, and shutter. Or.
2. Between, the front element of the rear cell, and shutter.
3. One or more spacers.
Repairing shutter is different story, though some LF photographers can repair minor things.