Optical Performance - Mamiya Super23 (Press) lenses

I have been using a Mamiya Super 23 for several years, in parallel with a Nikon F based system. The 100mm/f3.5 standard lens is superb and a good match for my Nikkor (105mm/f2.5) optics (square cm for square cm). Recently I obtained the 50mm/f6.3, 150mm/f5.6 and 250mm/f5 lenses (for an old camera, good bodies and most of the accesories are readily available on the S/H market) and would appreciate any comments on their relative performance.

I have found the Mamiya to be a very cost effective entry into medium format, particularly the flexibility of the backs (6 x 4.5, 6, 7 and 9cm). Although I haven't used the full features of the flexible back, I would like to begin with the cut film option and ground glass back. Information on optimum apertures and idiosyncrasies would also be much appreciated. Also comments on the use of the cut film system.

Thanks in anticipation

Peter Tredrea (Melbourne Australia)

Umm, not to be a curmudgeon, but you've got the lenses - why don't

you take a few rolls as a test and tell us how the lenses are? Also, any generic comments might not apply to the individual lens that you happen to have. That said, they all have a pretty good reputation.

Use whatever aperture you need to get the depth of field you need (note that the DOF markings on the lenses are about 1 stop optimistic,

or worse if you want to make really big enlargements).

<p>

If you want to use the back movements (or the extension tube set which is available as an accessory), you will need a ground glass back to focus, as the rangefinder is not acccurate once you start extending the back. It attaches and detaches like the roll film backs. You can

use 2x3 cut film in holders, though 2x3 sheet film only comes in a few

emulsions. I prefer to use the GG back with rollflm backs - you attach the GG, focus, then detach it and attach the rollfilm back.

Use a loupe to focus on the groundglass.