rangefinder problem

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I want to sincronize the top rangefinder and a 135mm lens on my Crown Graphic 4x5 camera. There is a flange in the rail that compress or release a cable as the user uses the focus knob. The cable comands the mirror in the rangefinder. The problem is that if I match the focus at infinity, it will be out at close range and the inverse is the same. The problem seens to be that the mechanism of the rangefinder needs a different distance to go from infinity to close range than the lens. If this is true changing the flange on the rail will have no effect. So, is there a way to change the course of the rangefinder or is it matched with only one lens size? Any imput will be welcome. Thank you

-- Rodrigo Tostes Malta (rodmalta@openlink.com.br), October 03, 2001

Answers

Rodrigo: The cams are different for each lens. If the Crown you have has a top rangefinder, the cams are underneath the rangefinder. Check the Graflex homepage for info.

REgards,

-- Doug Paramore (dougmary@alaweb.com), October 03, 2001.


Hi Rodrigo I've owned a 4x5 Crown Graphic with the later model top rangefinder and viewfinder for about 25 years. Much of the time its been stored. But a short time ago I changed my cam for a different length lens. Quick and easy, check and see if your viewfinder mask is a #4(fits 127mm to 149mm lenses). If it isn't, chances are you also have the wrong rangefinder cam. That could also mean you have the wrong rail gauge for your 135mm lens. On my camera each rail gauge is marked for which lens to use with it. Does yours? I have rail gauges for 135mm and 152mm lenses and the distance marks are different spaces (My 135mm gauge measures 23mm between 6 feet and infinity)(My 152mm gauge measures 28mm between 6 feet and infinity). Okay, you should really answer those questions above and put it on this thread before I could help any more. If you decide to remove the cam. First, it was not easy and was hard putting it back until I figured out the following: 1. It is NOT necessary to remove the rangefinder housing on top of the camera. DON'T! 2. The camera bellows must be extended so to clear the tube assembly plunger rod. 3. The cam cover assembly must first be removed inside the camera. 4. Replacing the cam. Make sure that the internal plunger is fully opened and slide cam into slot on tube and push under arm-rangefinder.

Okay, I'll be checking back later this month. Please tell us if you have any more iterest to continue. Harry

-- Harry L Martin (hmartin@tns.net), October 04, 2001.


Doug and Harry, thank you very much. I saw there is a black cover under the rangefinder, inside the camera, that opens and I was able to find the cam, a small piece of metal, with a hole off center and one angled side. It says it is a 90mm cam. As I have also an old angulon 90mm lens I will try to adjust the rangefinder to it. Any special procedures or should I just match the infinity adjustment in the ground glass and in the rangefinder and everything will be ok. It dont look so dificult to make another can. Do you have the dimensions of the 135mm can? Thank you very much again.

-- Rodrigo Tostes Malta (rodmalta@openlink.com.br), October 04, 2001.

There is no adjusting -- it either works correctly, or you need a different cam. It is at the same time the virtue and the curse of this model. Stephen Shuart frequently has used cams.

-- Bill (bmitch@home.com), October 04, 2001.

Rodrigo Yes, I have the dimensions for the 135mm CAM P5. Give me your mailing address and mail you a copy. I also have the June 1965 Graflex Service Instructions for the "45" which discribe the adjustment procedure using a Master Cam. What Viewfinder Mask do you have? And what is the measured distance on your rail gauge between 6' and infinity? Harry P.S. You can see a photo of my Crown Graphic on my web site:

-- Harry L Martin (hmartin@tns.net), October 04, 2001.


Rodrigo Yes, I have the dimensions for the 135mm CAM P5. Give me your mailing address and mail you a copy. I also have the June 1965 Graflex Service Instructions for the "45" which discribe the adjustment procedure using a Master Cam. What Viewfinder Mask do you have? And what is the measured distance on your rail gauge between 6' and infinity? Harry P.S. You can see a photo of my Crown Graphic on my web site: click here

-- Harry L Martin (hmartin@tns.net), October 04, 2001.

It wouldn't accept my link: www.angelfire.com/art/architecturalphoto

-- Harry Martin (hmartin@tns.net), October 04, 2001.

The rail gauge distance (6' to infinity)should measure something less than 23mm to fit a 90mm lens.

-- Harry L Martin (hmartin@tns.net), October 04, 2001.

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