How To Set Infinity Stops For Different Lenses (Graphic)

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Is there any information on the net as how to set the infinity stops for different lenses on a Crown Graphic. I actually have a 2.25"x3.25" camera, but I believe the procedure would be the same as the 4x5. I suspose setting the infinity stops would be the first step, followed by determining a focusing scale, and then calibrating the rangefinder. So I am a beginner and at square one.

-- John Daughtrey (johnd-gman@mindspring.com), January 21, 2000

Answers

Should be something at www.graflex.org. Their bulletin board was still off the air the last time I looked.

-- Tony Brent (ajbrent@mich.com), January 21, 2000.

It has also already been addressed here, if one would look in the Beginner's Questions section. The specific URL for this question is: http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=001AqV.

Richard

Moderator's note: fixed broken link.

-- Richard Rankin (rpr@coolabah.com), January 22, 2000.


Hmmm, that link doesn't seem to work properly from inside the message. So, go to Beginner's Quesations at the bottom of this page,scroll down about halfway inside that section and look for the subject:

Establishing and marking infinity stops?

Richard

-- Richard Rankin (rpr@coolabah.com), January 22, 2000.


Good camera repair people have optical benches and equipment that can do it scientifically. However, if you want to do it yourself it isn't difficult. Just get to some open space where you can see for at least a half a mile, preferably a mile, with something at that distance you can see well enough to focus on, then focus on it and slide the infinity stop back so it hits the front standard, tighten it down with a tiny screw driver, and you're all set. Just don't take the advice you sometimes see of focusing on something a block or two away. You need much more distance than that to be at true infinity.

-- Brian Ellis (bellis@tampabay.rr.com), January 23, 2000.

I did like Brian said, although you first need to adjust your focusing rail so that the two infinity marks line up on the fixed and movable scales. Then, with camera on tripod, focus on something as far away as possible by sliding the (unlocked) front standard in or out (not by turning the focusing knobs, which would move the scales from the infinity mark) until your subject is in focus, then lock the front standard, and then move the loosened stops up against the front standard, then tighten the set screws. Do this for each set of stops you have for your different lenses.

-- Ron Shaw (shaw9@llnl.gov), January 24, 2000.


Also - use a carpenter's square (I like the kind with the adjustable squaring arm) to make sure that BOTH stops are the same distance from the ground glass so that you front standard stays square with your rear standard. This works with both the miniature crown graphic and the 4x5.

http://www.graflex.org/speed-graphic/kalart-adjustment.html

The above page will tell you how to set the rangefinder. Graflex.org also has info on the focus scales but I have yet to find a retailer who will sell me specific pre-printed scales for specific focal legnth lenses --- I'm making do with a home made one for now.

-- alan dale (adale6@excite.com), March 21, 2000.


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