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paxety · Joined: 10 Sep 2003 Posts: 69 Location: Florida

I have a strange stripe on my negatives. 4x5 Anniversary Speed Graphic with the 127mm Ektar, Graphex shutter, Graphic back. It happens with all film holders and does not happen with the same film holders in another camera.

The stripe is about 1/4" wide. Looking at the back of the camera, the stripe appears on the right side - the side from which the film holder is inserted. It's stronger at the bottom (of the camera) than at the top. It's only visible when in a smooth area, such as sky, field of grass, etc.

When I first saw it, I thought light leak. But no. The stripe is LESS density on the negative, where a light leak would be more density. In other words, the stripe would be darker on a print. The stripe area also contains some detail, so some light is getting through.

I've removed the camera back and can see nothing obstructing the light. Does anyone have any ideas as to the cause?
j.e. simmons

t.r.sanford · Posted: Thu Mar 25, 2004 3:30 pm Post subject:

Might this be caused by one of the pleats of the bellows, on one side, extending very slightly into the cone of rays formed by the lens? At a certain distance behind the lens (probably nearer the back than the front), this might not obstruct the image entirely.

Have you observed whether the choice of aperture has any effect on the phenomenon?

paxety · Joined: 10 Sep 2003 Posts: 69 Location: Florida

That makes some sense - I'll check further. I do not see that choice of aperture makes a difference, although I do not recall using the extreme ranges. I've probably mostly used f/5.6 - f/16.
Thanks,
j

paxety · Joined: 10 Sep 2003 Posts: 69 Location: Florida

That makes some sense - I'll check further. I do not see that choice of aperture makes a difference, although I do not recall using the extreme ranges. I've probably mostly used f/5.6 - f/16.
Thanks,
j

disemjg · Joined: 10 Jan 2002 Posts: 474 Location: Washington, DC

Put the camera on a tripod, pointed at the sky, stop down and check to see if an area of uneven illumination is visible on the ground glass.

I presume you have already looked inside the bellows to see if indeed something has come loose and is blocking the light?

And, while you mention your Supermatic, are you using the lens shutter or the FP shutter? If the FP, then carefully inspect the curtains to be sure they have not developed a problem. You will need to remove the spring back to do a proper job of checking the curtains; look at the inside of the bellows from the back while you are at it.

troublemaker · Joined: 24 Nov 2003 Posts: 715 Location: So Cal

My inclination, provided you are useing the FP shutter, would be to check the curtain and windows for a loose piece of fabric or something that may be flipping up across the window (forgive me if my terminology is wrong) when it is released under spring load. Check front and back, and all around the frames. Run it throught the speeds if you can with a light on it. If it happens when using a leaf shutter,and nothing is between the lens and film, I would then try turnung the lens 180 degrees and try again. The sky check sounds good and I would try direct and difused light also with a loupe.
good luck