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zoom2zoom
13-Mar-2010, 13:51
i just acquired a fotoman 624 with schneider 210mm f5.6 lens, but i noticed that the focus ring will not focus beyond 70ft and there is still about quarter turn to 300ft and infinity.

without ground glass, i can not confirm if 70ft is infinity, and i can not calibrate the lens focus. is there another way to do this?

from the manual, once i determine the infinity distance, i can then adjust the distance scale ring to align the infinity symbol with the red distance indicator line.

i suppose i can take rolls of test film to determine distance, but i am just wondering if there is another way to do this.

thanks in advanced.

IanG
16-Mar-2010, 02:10
Get a piece of glass cut to fit the back, it doesn't need to be the full length, it's very easy to grind your own screen, while 400-600 Silicon Carbide grit is the best you can get some fine valve grinding paste at an auto-store. It'll cost you very little and better than the $195 for the Fotoman screen. Just tape it in place. A Google search will tell you how to grind the screen it'll take less than 10 minutes

Alternately use a TLR focus screen.

Ian

JRFrench
16-Mar-2010, 02:23
http://www.dokasphotos.com/techniques/ground_glass/

I have done this, it works very well. The grain is slightly finer than the only commercial screen I have seen, from a Shen Hao.

GPS
16-Mar-2010, 03:00
Forget completely about grinding your own gg - too much work for a one time application. Instead, cut a piece of Plexiglas, stick on it a frosty Scotch type and enjoy your focusing gg!