Mamiyaflex II, crossing my fingers

Got this camera for just $20 so my investment is small. All mechanical functions work very well but cosmetically only fair. It's a an early Mamiya product from 1952 before the C- series. The lens is an unfamiliar one, at least for me, an F=7.5cm, 1:3.5 Setagaya Koki Sekor which I have been led to believe is a 4 element lens. The focus is front geared with just a 1/4 turn from 3.5 ft to infinity. Initially when I got it the viewng lens stuck out much further than the taking lens and was bad at infinity. I adjusted this and attempted to match the two lenses(using Magic tape as a focus aid). I thought I had done so until I took my first roll--the edges were unacceptable and center was not great either in all the images. I did not expect Rollei like sharpness but this was bad.
I was about to make this a shelf camera but I decided to try looking at the taking lens and unscrewed the whole thing. I experimented with rethreading several times and my hunch is the previous owner misthreaded(?) the taking lens. Now the viewing and taking lens mesh perfectly. Will try another roll of HP5+ to check the results. Hopefully Got myself a decent camera afterall. Will give an update.

Dan0001 said:

I adjusted this and attempted to match the two lenses(using Magic tape as a focus aid).

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Magic tape is not good enough. This, from my personal experience.
Use a ground glass.
Also, my suggestion is, don't calibrate using the widest aperture (f3.5); try to calibrate using f8 or at least f5.6.
These lenses usually have some focus shift so if you calibrate for sharp center at f3.5, results might not be so good (over the full frame) at narrower apertures.

Ground glass my be tricky to cut to size. I make myself a 'faux' ground glass from a clean CD jewel case. Cut a piece of jewel case to size, just overlapping the film rails. Then place strips of magic tape butted up to each other on the piece of plastic. When using place the tape side of the plastic facing the rear of the lens, i.e. at the film plane. You can tape the plastic at the ends to the film chamber so that it stays in place while you check and adjust your lens.

I used to have a Mamiyaflex C2 and I always liked that camera very much. Midwest Photo gave me the camera for nothing when I walked in one day. It needed a good cleaning and I cut new leather, using a paper pattern, and stuck it down with Elmer's glue. I always wanted to try the earlier Mami's, they do look like a lot of fun to use. I do think the lenses are probably pretty good, but need some attention and patience to set up right.

Looks like you are on your way to having a good one. Not bad for $20

flavio81 said:

Magic tape is not good enough. This, from my personal experience.
Use a ground glass.
Also, my suggestion is, don't calibrate using the widest aperture (f3.5); try to calibrate using f8 or at least f5.6.
These lenses usually have some focus shift so if you calibrate for sharp center at f3.5, results might not be so good (over the full frame) at narrower apertures.

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I have used a thin tracing paper purchased from a local art store - tape it across the film plane. Much less flimsy than strips of tape.

I use a small sheet of groundglass which I cut to size myself. Architects Vellum or photographic diffusion sheeting (for hot lights) can also work

After making some slight changes noted above and developing my latest roll of HP5+, I have to say the results are only marginally better. This model of Mamiflex II also came with an Olympus Zuko lens and reportedly a superior lens(collectors seem to prefer it anyway). It would be interesting if I could ever swap the current lens with a Zuko to compare but that it is very unlikely. I may play with this one some more but my expectations are not very high.

excelent tip....

drafting velum works very nicely as a ground glass.

tokam said:

Ground glass my be tricky to cut to size. I make myself a 'faux' ground glass from a clean CD jewel case. Cut a piece of jewel case to size, just overlapping the film rails. Then place strips of magic tape butted up to each other on the piece of plastic. When using place the tape side of the plastic facing the rear of the lens, i.e. at the film plane. You can tape the plastic at the ends to the film chamber so that it stays in place while you check and adjust your lens.

Click to expand...

That's a good trick and one I might try in the future. I've ground a few sheets of glass from cheap picture frames, and being able to use plastic would be beneficial. The glass is a bit too sharp and fragile for my taste.