90mm Schneider 4x5 lens problem?

[ColonelKurtz]

Welcoming opinions on possibilities for the cause of this light leak on my 4x5 sheet film... It looks like it could be a lens issue, but I realize its very difficult to tell, and that the process of elimination, gear wise, will help narrow this down. Any input is welcomed and appreciated. Thanks

[Mark Woods]

Put the film back in the holder in the orientation it was when you shot the image. Set the bellows distance the same as it was when you shot it. This will indicate where the light exposed the film. You can then search in that particular area for the problem. If the problem isn't immediately noticeable, then use a directional light (or flash light) aimed at where the light leak is. You should be able to see the light on the film in the holder. If not, it may be that there was something compromising the light tight ability of the camera/film holder that was a one off. This would be particularly true if this is the only image ruined in this manner.

I hope this helps.

All the best,

[ColonelKurtz]

Thanks, Mark... I've checked everything as you recommended, and my only guess is the film was compromised at some point when it was not in the camera. Using a camera with a brand new bellows, and I checked with a flashlight, etc... Checked the film holders, as well. Can't find anything.

[Mark Woods]

Have you processed another sheet of film directly out of the box to see if it's the film and not the camera?

[ColonelKurtz]

I only made that one picture... A weather system passing through Angeles Crest (not far from you) 3 days ago gave me about a 10 minute window between downpours to make just that one picture. I'm going back up there on Saturday to try and try again.

[Mark Woods]

You really might want to process one sheet of film directly from the box to see if it's a film problem and not a camera problem.

[ColonelKurtz]

Will make sure I do that. Thanks for the tip.

[Mark Woods]

:-)

[ottluuk]

Condensation/fog on part of the front element, perhaps lit up from the rear by an unfortunate internal reflection?

I wouldn't rule out something like that if you can't trace it to a film or light leak issue.

[Doremus Scudder]

If this were a lens issue, I would think that any light leak this bad would be visible on the ground glass when composing the image. Since it is in the top right corner (o the side that the darkslide likely was) I would bet that the back was inadvertently pulled away from the camera body when pulling/inserting the darkslide. The remedy is to pinch the back to the camera body with one hand while pulling/inserting the darkslide.

If that's not the problem, then perhaps a loading/processing accident led to exposure. I can't see if the rebate is exposed by the leak or not, but if so, it likely happened out-of-camera and vice versa.

Do do the check Mark suggests with a flashlight or the like to check for leaks though.

Best,

Doremus