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View Full Version : Are colour bands on my 4x5 transparencies light leaks?



Craig Joiner
11-Aug-2009, 05:35
What have I done wrong?

Ebony RSW45, brand new Toyo holder, Fuji Provia 100F. Sunny day, but with sun behind me. I made 2 exposures and the more prominent left hand band was on just one and the weaker right hand bands were on both. Both sheets were in the same holder.

I've seen similar colour bands on the odd transparency (different holders) but nowhere as bad and up until now I had wondered if they were a mess-up at the lab, but I'm now thinking these are light leaks. How light tight are holders? Could it be a result of leaving them in direct sunlight while setting up the camera?

Any thoughts?

sgelb
11-Aug-2009, 05:39
wow fuji is so RED! i think thats holder or fog/film issue. what holder are you using? did u possibly open the box in daylight or did it get moved around? is the film super old? hard as fuji puts its product in those black bags as well.

Archphoto
11-Aug-2009, 06:25
Q's:

1) was the bellows mounted correctly ?
2) is your bellows still light-tight ?
3) was the filmholder seated correctly ?

Both could have caused this type of fogging.

Peter

rdenney
11-Aug-2009, 10:13
What have I done wrong?

Ebony RSW45, brand new Toyo holder, Fuji Provia 100F. Sunny day, but with sun behind me. I made 2 exposures and the more prominent left hand band was on just one and the weaker right hand bands were on both. Both sheets were in the same holder.

I've seen similar colour bands on the odd transparency (different holders) but nowhere as bad and up until now I had wondered if they were a mess-up at the lab, but I'm now thinking these are light leaks. How light tight are holders? Could it be a result of leaving them in direct sunlight while setting up the camera?

Any thoughts?

It sure looks like a light leak to me.

But the banded nature of it suggests against a pinhole in the bellows, or a problem with how you load the holders. The fact that you had some problem on several holders suggests against a particular holder. The fact that the bands are in the same place on transparencies from several sessions suggests a systematic problem, not a blunder from one film-loading session.

I would suspect a light leak along the rear standard, around the opening for the film holder or where the bellows is attached. Remove the ground glass, and in a dark room, insert a light bulb into the camera from the back. Drape a dark cloth over the opening. That's how I've found light leaks.

Rick "thinking the bellows attachment the most likely possibility" Denney

benrains
11-Aug-2009, 12:16
Another possibility would be that the camera's back wasn't seated properly. Most field cameras have the option to remove and rotate the back to either a horizontal or portrait orientation. If the back isn't snapped in snuggly you might get this sort of leak.

Ken Lee
11-Aug-2009, 13:21
... or when you remove and replace the dark-slide, there is a brief and slight movement or looseness.

Even if your camera has a spring or bale-back, this is easily possible - especially if the dark-slide itself is stiff, as many are whether new or old.

I learned here, that even with the best camera back, it's best to hold things shut with one hand, while inserting or removing the dark-slide with the other hand.

Hiro
11-Aug-2009, 15:08
There may be a different cause for each.

With the weak band on the right, I would think it's a light leak caused by the camera as well. It would be quite difficult for the light to reach an inch into a loaded film without affecting the edge. If the camera leak is very minor, you may not always notice the slight loss of contrast on the film. Strong sun (from above and reflection from below) pronounces the problem, and that's how I once realized there was a leak.

The more prominent one on the left edge appeared only on 1 of the 2 recent exposures, which makes me think it's improper seating/handling of the holder and such, i.e. an irregular problem as opposed to consistent leak caused by the camera. As noted it's not too difficult to cause a leak while inserting/removing the holder.

Film holders should be "light tight" under normal handling conditions although I don't know manufacturers' test standards. As a precaution, I do keep holders out of direct sun (or any) light until I'm ready to shoot. Even with 35mm rolls, I remember they recommended changing the film with your back to the sun. You could test them, for example, by leaving loaded holders (with unexposed films or print paper) under the sun.

Craig Joiner
12-Aug-2009, 01:53
Thanks for all the helpful replies.

I am sure it's not a film issue given it was new stock and I don't break the seal of a new box until I am actually loading it into holders. I always load the whole box because I know what will happen with a half full and unsealed box lying around!

From the replies above I suspect this was simply caused by sloppy handling of the film holder/camera back on my part. Given I'd rotated the back for this shot I wonder if I'd forgotten to close one of the two securing locks. Since this shot I've been very careful when mounting the back/film holder and so far this hasn't occurred again.

However, thanks to Rick's light bulb suggestion I will be testing for light leaks just in case.

Thanks again.

Craig Joiner
12-Aug-2009, 01:56
There may be a different cause for each.

With the weak band on the right, I would think it's a light leak caused by the camera as well. It would be quite difficult for the light to reach an inch into a loaded film without affecting the edge. If the camera leak is very minor, you may not always notice the slight loss of contrast on the film. Strong sun (from above and reflection from below) pronounces the problem, and that's how I once realized there was a leak.

Interesting. I'll be sure to check for light leaks now.

Glenn Thoreson
12-Aug-2009, 11:21
Two rules you should follow:

Don't leave your film holders in the sun. Keep them in a bag or something until you're ready to shove it in the camera. Handle with the opening pointing down.

Cover the camera with your dark cloth after you focus. Pull the slide under the cloth.

You'll have a lot less trouble. :D

William McEwen
12-Aug-2009, 11:26
Beautiful view, by the way.

Hiro
12-Aug-2009, 13:27
Cover the camera with your dark cloth after you focus. Pull the slide under the cloth.
I covered the entire camera (minus the lens) with the dark cloth (black T shirt) and clips when I had the problem. I still do this (minus clips) as a habit.


Beautiful view, by the way.
Truly.
A couple of years ago, I planned a visit to Wales during the Cardiff pool of RWC preliminaries (sorry, I'm rather a Wales supporter :D). Between matches I hoped to spend some time on the English/Welsh coast with a camera but had to cancel the whole trip due to a run-on project work. The image reminded me of what might have been.

Craig Joiner
13-Aug-2009, 10:34
Beautiful view, by the way.


Truly.

Thanks guys!

It was even better a few days later when I took this one (http://www.craigjoiner.com/library/image/I00006b7J6c6jvL0) and no light leaks in site!