How do I set the infinity stops and calibrate a Kalart rangefinder on a Speed Graphic?
Asked 5/20/2017
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I’m trying to recalibrate the Kalart rangefinder on a Speed Graphic. The front standard can be positioned in two ways: by moving it along the bed rails and by moving the lens in its focusing mount, which makes the setup confusing.
Near the camera body there are scales and what appear to be infinity stops. I’m not sure what the different scales mean or where the lens is supposed to be locked before adjusting the rangefinder. Since the rangefinder only responds when I move the front standard on the rails, I’d like to know the correct procedure for setting the lens position and infinity point so the rangefinder can be calibrated accurately.
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
9y ago
2 Answers
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On both sides of the rails, very close to the camera are flip-over stops, one on the right, one of the left. When you open the closed camera cover, you pull the lens forward until it contacts these stops. The stops have been previously adjusted as to their position. This act correctly positions the lens for infinity focus. You can override by flipping these stops over. Now the lens can be freely moved forward of this infinity position. To re-calibrate, the infinity stops are locked in place with a screw. Loosen the screw on both infinity stops. Slide them far forward. Set the purple circled scale index so the index mark aligns with the infinity symbol. Set the shutter to "T". Focus using the ground glass on a distant tree. Use a 10X magnifier to assure tack sharp focus. Once achieved, slide the infinity stops to the rear. They are positioned to rest against the structure holding the lens board. Tighten the set screws. You can repeat to improve this adjustment.
Originally by user44949. Source · Licensed CC BY-SA 4.0
user44949
9y ago
0
Generated from our catalog & community — verify before relying on it.
Yes—on a Speed Graphic the Kalart rangefinder is calibrated with the front standard placed at the camera’s infinity stops on the bed rails.
Those flip-up stops on each side of the rails are the key. When opening the camera, pull the front standard forward until it hits those stops; that establishes the standard’s infinity position for that lens. If you flip the stops out of the way, you can move the standard freely beyond that point.
Typical setup procedure:
- Loosen both infinity stops and move them forward.
- Set the bed/track distance scale index to the infinity mark.
- Open the shutter on “T” and focus on a very distant subject using the ground glass, preferably with a loupe.
- When infinity focus is sharp, slide the infinity stops back against the front standard and lock them.
- After the infinity stops are set, adjust the Kalart rangefinder to agree with that position.
The important point is that the rangefinder couples to the front standard movement on the rails, not to any focusing movement in the lens/shutter assembly itself. So first establish and lock the correct infinity-stop position for the lens, then calibrate the rangefinder from there.
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AI9y ago
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