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Phillip Noll
10-Oct-2004, 09:35
I've just entered LF photography. Purchased a new Shen-Hao 4x5 and a new Fuji Quickload Holder. My first chromes all show a light leak. I've taken the camera into a dark room and used a bright light to look for leaks but can find none. I extended the bellows, retracted the bellows, inserted a film holder, went through all the motions of taking a photo while using the bright light to search for leaks but still could not find any. I also ensure that the holder is properly seated on the back before I expose the film (i.e., the ridge on the holder is in the groove on the back). I have posted thirteen 4x5 chromes that show various leaks at:

http://home.earthlink.net/~shinumo/

One third of the frames appear to be fine but the remaining 2/3 are fogged. It seems that when the sun is in front of me or to one side or the other, the light leak is greater than if the sun is behind me or I'm shooting in overcast conditions.

If you look carefully at the very top edge of frame #1 and you will see a thin strip of the photo that did not receive the light leak. Strange! Frames #1 and #2 are the same shot. As are 4+5, 7+8, and 10+11. Meaning I did not move the camera between shots. Just loaded a new QL.

Also, frames 10 and 11 were shot vertically and there is only a very small light leak at the top of the frames (end with the ID notches). This is also the end of the film that is near the metal clip on the QLs.

Would appreciate any input you all care to share with me. Thanks!

Andrew O'Neill
10-Oct-2004, 09:56
Hi Phillip,

I've never used a quick load but I would suspect that it is either a holder seating problem, or a problem with the holder itself. Do you have any holders that you load yourself (Lisco/Fidelity type)? Load some colour film and expose them on a sunny day (would be better to use b/w RC paper cut to fit as that would be cheaper). If you still see leaks then it is a problem with your camera or seating. It's not bellows because the leaks are almost identical. If you see no leaks, then your quick load is probably the problem. Are you sure the camera is not leaking from the lens board? Put a bright flash light inside your camera with a holder and lens with shutter closed. Flick the lights off and take a look. I really can't thing of anything else.

Gem Singer
10-Oct-2004, 10:51
Hi Phillip,

From my experience with the 4x5 Shen Hao, check to make sure the bellows frames are attached properly to the front and rear standards. I noticed that the pointed ends of the rear retaining screws for the bellows slipped out of their proper position if I didn't hold the bellows firmly against the rear standard while tightening the knobs. That could be the cause of the light leak you are seeing.

Bruce Watson
10-Oct-2004, 11:14
Sounds like Eugene may have the anwer. The way that fogging occurs (straight line cutoff, part way into the frame) looks like the light is entering where the bellows attaches. The rear standard between the film cut out and where the bellows attaches to the standard is "thowing a shadow" which is why the entire frame isn't fogged. This would also help explain why the leak is more intense when the bellows gets some sun and less intense when the bellows is in shade.

Brian Ellis
10-Oct-2004, 11:58
I've never used the Quickload holder but I've had light leak from the top of the holder in vertical orientation when I pulled the dark slide and left the holder uncovered in bright sunlight too long. I've also had light leaks from pin holes in the bellows. On the film neither problem produced the results that you have here. OTOH, when I failed to properly reinstall the normal bellows on an Ebony camera after having used the bag bellows, as I recall I got results that looked a lot like what you have here, especially in the inconsistency of the areas where light leaked in. I'd guess that, as Eugene suggested, your problem is with the installation of the bellows.

Jorge Gasteazoro
10-Oct-2004, 12:34
I have had this same type of problem and it was due to a improperly seated holder. But I guess a badly attached bellows could also be the cause.

Rick Heitman
10-Oct-2004, 16:36
Phil, The quick way to check what these guys are sayin is to cover the back standard with your cloth and see how the photo looks, if it is still there , cover the front standard. if you still have a leak, cover the film holder. I would think that one of these photos will work and you should be able to find it from there.

Phillip Noll
10-Oct-2004, 17:45
Here's the latest:

Bought some Polaroid 52. Picked a composition with the sun at my back. Loaded a sheet of 52 and exposed it. No light leak evident on the print. I then put a sheet of 52 into my Fuji QL holder and exposed it (Yes! I was actually able to get the Polaroid sheet out of the Fuji holder!). No evidence of a light leak on the print. The two are identical. I then picked a composition facing the sun but kept the sun out of the frame (above). Did the same experiement with two sheets of 52 and the two film holders. No light leaks and the two prints are identical. There is some lens flare (hexagonal) but that doesn't bother me.

This tells me that there is nothing wrong with either holder or the camera! I will shoot up the rest of the box of 52 tomorrow to confirm my findings of today. The only thing I can think of is that I removed the bellows after I shot the chromes referenced in my original post to check for pin holes (found none). Then I replaced the bellows. I noted that I had to press on the end of the bellows fairly hard to make sure the retaining screw held the bellows in place properly. I guess its possible that the bellows was not seated properly for my first shots and that it is now properly seated.

Opinions?

Jim Rhoades
11-Oct-2004, 05:12
Phil, You say you exposed the film during these tests. You may want to try testing by racking out the bellows all the way. Pull the paper slide and not make an exposure. Rotate the camera around on the tripod in full sun taking a few minutes. Re-insert the slide and pull and process. The film should be black. Any small pinhole will show up as a white dot and a holder or bellows attachment would be a major white slash.

Paul Butzi
11-Oct-2004, 09:16
It's interesting to note which end of the film is fogged - the end away from the film notches, which is the end of the film closest to the 'mouth' of the holder.

One possibility which hasn't been mentioned is that you're pulling the film holder backwards when pulling the packet/dark slide, with the result that you generate a brief light leak that flashes the film. The rather abrupt edge to the fogging in some cases makes me suspicious that it's this sort of a leak, and not a bellows problem.

I'd try setting up the camera, putting the empty Quickload holder into the back, and then looking in through the front of the camera (no lens in place) and pushing/pulling on the mouth end of the holder, and see what sort of light leak you get. If you get a spray of light that comes in the open gap between the film holder and the camera back, and there's something that makes an abrupt edge to the light spray (like we see on the sample chromes, particularly #'s 3,4,5,6,7,8) then I'd guess you're pulling the back away from the camera briefly when working the darkslide.

A problem with the light trap on the Quickload holder might also produce fogging like this, but your results with the type 52 seem to rule that out, although the packet thickness is different.

It definitely is NOT a pinhole leak. If I had to bet, I'd bet the holder is coming away from the camera back either when you pull the darkslide or when you run it back in. If that wasn't it, and I had to bet again, I'd bet that it was a leak along the bellows frame/camera body joint.