Mamiya C330 Lenses

[Ryuji]

It seems the shims which came with the lens were not correctly installed. The same lens was returned and was "tack sharp" when he next used it, said this was a common problem with the lenses. The glass was excellent, but the shims would normally be out of adjustment due to an improper c.l.a. or tinkering by someone who didn't understand the lens.

This seems to me to be simply a manufacturing issue from years ago. With today's technology and tolerances, the use of shims would be an unacceptable,costly and unnecessary manufacturing procedure. In the past, it was just a necessary part of the "system" for production. tim

In Mamiya TLR’s, shims are also used to align viewfinder screens... as a general suggestion, do not disassemble the viewfinder chamber, even if it is dirty. There is little to gain and a lot of risk to misalign the screen.

[PeterB]

In Mamiya TLR’s, shims are also used to align viewfinder screens... as a general suggestion, do not disassemble the viewfinder chamber, even if it is dirty. There is little to gain and a lot of risk to misalign the screen.

As other posters have encouraged people to do and as detailed here, I have already replaced the foam under my focus screen. It was deteriorated, but interestingly not enough to lose enough springy-ness and be the cause of the problem.

[Ryuji]

I have two Mamiya TLR lenses that I don't use because they weren't sharp from day one. I bet missing or incorrect shim is a suspect, as they look clean and they make reasonable images. So, does anyone know the contact of current Mamiya service (does it still exist) and how much it costs to get them fixed?

[Ryuji]

Oops, the viewfinder of C330 is very different from mine, C3. In older models, the alignment of viewfinder screen was determined by the number of tiny thin washers on ALL of 6 or 8 (forgot which) screws that retained the screen assembly. It is crazy. I had to calibrate the screen alignment when I could see moon from the window of my studio.

[RidingWaves]

Peter, I just posted on your photonet post regarding this. Your chrome shim looks like factory. The black one looks suspect, that is one thick a** shim! Something is amiss, I know the first thing I would do is do a test without that black shim.
The spring lock being off by large amount still troubles me. Show a few shot where that was and how you fixed it.
Christiaan

[PeterB]

Thanks Christiaan. I'll limit my responses to this thread and summarise here once I have solved the problem.