Original post: On March 22, 2012, Education and concerning use with 3x4
http://graflex.org/helpboard/viewtopic.php?t=6264&start=0&postdays=0&postorder=asc&highlight=
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Take 2: Use with a 4x5, Reassembled 1950 Pacemaker:
Both lenses are VII 35cm lenses.
From original post, Dan Fromm stated

Quote:

"Your lens is a double Protar composed of two "Protar lenses" (Zeiss parlance). With both cells in place, its focal length is is around 180 mm. Each of the two cells can be used without the other. One has a focal length of 290 mm, the other 350 mm."

Reference: p36 & 37
http://www.cameraeccentric.com/html/info/zeiss_4.html
Now on p36,, it shows the Series 1, 2 & 3 with pictures I, II, III
On p37 it gives clarity of how this was achieved.

Realizing that the lens really wants a 5x7 format, I still would like to set up the Rangefinder, for this lens. So did a quick, lets take a look, and focused with both of the Portar lens on, there was of course no problem in focusing.
Then took off the front one, leaving the rear one on. Could not focus!
Put the front one back on, with the rear off, and could focus.
Question:
1) I can get the shortest focus and the longest focus, but not the intermediate focus! The obvious reason to me, is the bellows is not long enough to allow the circle to be brought into focus, because the lens is to close.
Theoretically, (do not wish to do this, as I wouldn't be able to close the camera), .. I could make an extended lens board, and be able to focus all three, if the long focus didn't run out of rail, which it well could. ... Am I perceiving this correctly?
2) Want to verify... The Rangefinder can be only adjusted for one lens. In a sense, I have two configurations with this one lens, that I can use on the 4x5. So, essentially its two lenses. My choice would be to set the Rangefinder for the long focus, and then use the ground glass for the short focus.
Or is there another way?

Peter, too long means too long.

Look into making an extension tube. If you do, make sure to line it with flocked paper or felt, otherwise the lens will give you dazzling flare.

Dan, ur so cryptic..

Quote:

Peter, too long means too long.

It took me an hour to finally get your message..
Nuts.. the Rangefinder is not going to work with this lens, cause its to long, even at its shortest focus.
NUTS!
I have no problem with using the ground glass, excepting that it easier with a tripod, and have not yet trained myself with the T shirt method, and using some sort of loupe glasses.
Learning can be habit forming when going to new territory.
So the longest lens that can be adjusted, in the Rangefinder is about 165mm?