Light leak diagnosis help please.

[Sam McRae]

Hello, I am wondering if anyone has seen a light leak like this one. I am shooting with a Zone VI studios 4x5 view camera. It's an original one from Vermont.

It does not occur with every shot, but about 50% of them. Maybe because I leave the dark slide out for longer on some exposures? It is occuring with multiple film holders, multiple boxes of film, and two different lenses. I have put a light in the bellows, in a dark room and was unable to see any leaks. I am curious as to how the leak is so uniformly even in luminosity from edge to edge.

The example I uploaded is a quick scan and the problem is the stripe of overexposure from left to right.

Is it clearly a leak in the bellows?

Thank you very much,

Sincerely,

Sam

[consummate_fritterer]

What stumps me is, not only is it unique as far as light leaks go but its also magenta in color. Are you absolutely certain it's not a processing error? What kind of film? Where was it processed?

[Jim Michael]

What manufacture of film holders where problem has occurred? Metal dark slides? Also is the edge fogged?

[Sam McRae]

What stumps me is, not only is it unique as far as light leaks go but its also magenta in color. Are you absolutely certain it's not a processing error? What kind of film? Where was it processed?

I thought it may have been a processing error until a second lab got the same results. Portra and Ektar both got those results. Not sure which of those films this is. Disregard the magenta. It's probably the quick scan and the stormy weather. The colours in other shots, with and without the issue, have been very accurate in colour.

Thank you.

[Sam McRae]

Hi, they are old metal dark slides. I'm not sure of the manufacturer. If it were a problem with the slides then how would the leak be so even in luminosity from edge to edge? Also I get the same leak in different film holders. Also, there have been no fogging issues in other negatives. I'm not sure that there is here. I could post other photos with the exact same leak. Thank you very much. I order the film from b&h shipped to Canada so I thought that border xray might be the culprit, but then why would it only be some negatives and not others and the exact same overexposed band position in multiple boxes of film?

Thanks a lot,

Sam

[chassis]

Consistency across film types, film holders and lenses points to the camera in my mind.

Can you 100% rule out lens flare? The light seems to be coming from camera right. Likely a small possibility, but are you sure it is not flare?

Are you 100% positive that the film holders were firmly seated in the spring back? I don't know the camera you are using. I went through a period of light leaks, when I was getting to know my Toyo 45AII, and I was not seating the film holder firmly in the back, and not closing the back firmly on the film holder. It's easy to do. I now do a check, after inserting the film holder, to be sure it is seated and secure in the back. No more light leaks.

If the light is coming from camera right, the defect is generally oriented toward the light source, which would be consistent with a camera-related leak.

[Gary Beasley]

Do a pinhole test on the camera using a light inside the camera in a darkened room. It almost looks like the band is a very fuzzy version of the skyline which suggests a tiny hole on the lensboard to me.

[consummate_fritterer]

Do a pinhole test on the camera using a light inside the camera in a darkened room. It almost looks like the band is a very fuzzy version of the skyline which suggests a tiny hole on the lensboard to me.

Excellent diagnosis.

[Graham Patterson]

Sounds right. An even light strike on the film almost has to be from the front of the camera. If it is the lens board area, then the effect should be the same position relative to the camera, and irrespective of the film holder orientation.

[Sam McRae]

Thank you very much everybody. Before the plea for help I had gone in the darkroom with a light in the camera but I couldn't see anything. I will try again with a brighter light. I will post my results when I figure it out.