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View Full Version : What did I do wrong here? Light Leak in holder or lens flare?



GabrielSeri
25-Feb-2011, 19:23
Please explain to me what I did wrong here. This was taking last weekend in Joshua Tree with my 5x7, first photo weekend out with the new camera. This was going to be the shot of the weekend as I told my wife when I took it. Now, I know I should have taken a duplicate..
Is this a light leak on the 5x7 holder? Or is this some kind of lens flare on my single coat lens (Fujinon 250mm 6.3)? I know it's not a pinhole issue because my other shots have come out perfectly. My next thing I do will be to reshoot with the same holder to see if the effect repeats.
Thanks for answering.

"LF photographer in training"

Gabriel
http://www.silverpiscis.com/Photography/JoshuaTree2011/elephant5x7_1BAD.jpg

Gem Singer
25-Feb-2011, 20:21
Looks like flare.

Unusual for holders to leak on the sides. They usually leak at the ends.

Appears to be a shot into the sun with a single coated lens.

Did you use a lens hood (shade)?

Filmnut
25-Feb-2011, 20:36
I would say flare too, but I am puzzled by the vertical shape, could there of been an internal reflection of some kind? Or a leak from the lens board? The last is a bit of a stretch, I think, but I had a board that didn't fit right once, and caused me some grief. let us know if you used a hood on the lens.
Keith

GabrielSeri
25-Feb-2011, 21:11
Hi guys. No hood. The camera is really new and I'm not finished buying all my accessories. ha. The filter size is 67mm I should be able to find a good hood at that size. I had a feeling it was lens flare, it's weird how it's so straight.

vinny
25-Feb-2011, 21:47
That's not lens flare. Too even. Light leak of some kind somewhere along the line.

Preston
25-Feb-2011, 22:05
Doesn't look like lens flare to me, either. There is also a spot toward the left side of the posted image.

You might try taking the holder into the darkroom, opening it up and shine a bright pen light into the film slot and look to see if you see any light from the outside; sort of like checking a bellows for pinholes. If you have one of those laser pointers, that would be an ideal point source. You might also check to see if the holder is slightly bowed. It may not be seating quite right in the camera.

--P

GabrielSeri
25-Feb-2011, 22:34
I just checked and this happened on 2 different holders. I did 3 shots and on all 3 shots I get this same discoloring. I will do the darkroom holder light check and look at the alignment of the holders, but I think my best test would be to reshoot with these 2 holders and see if they leak again? I will use a lens hood this time even though it will be a different shot.

Thanks for the help.

Brian C. Miller
25-Feb-2011, 22:44
Check your bellows. Not exactly a pinhole, but something else. Since it occured on different holders and different shots, then it isn't the holders or darkslides. It could be the back, or something like that.

Put the holder in the camera, and then take off the lens board. See if you can spot the light leak in the sunlight, looking in through the lens board opening.

PS - good composition! I like it.

GabrielSeri
25-Feb-2011, 23:03
Hi Brian, but if it is the back why did it happen only on this shot that weekend? All my other shots came out good with no strange effects at all. I will do your test tomorrow in the day time.

Thanks I liked the composition too, I had a feeling I had a winner and I told my wife and then was destroyed when it didn't come out as I wanted. Oh well, will have to reshoot. I took a similar photo with my 4x5 years ago and I wanted to recreate it with the 5x7. http://silverpiscis.com/Photography/portfolio/elefante2.bmp

Brian C. Miller
25-Feb-2011, 23:09
Hmmm, the second image you posted (good one), the light is behind you, while with the other one the light is in front of you. It could be that the leak is at the back of the bellows. When I got my Calumet C3 8x10, the bellows tape was old and needed replacement. This could be happening with your camera. Actually, if it's the tape, then a visual inspection should be good.

Are your holders wooden or plastic? If they are wooden, then the holders could have been compressed at some point, so that could cause a light leak, too.

mandoman7
26-Feb-2011, 05:42
Leaks in holders will always show at the edge of the image. There's no way for there to be a leak in the middle of the image and not along the side. The light would travel in from the edge with a holder leak, so the streak you're showing in the first image cannot be from the holder.

It doesn't look like lens flare either, which happens in round shapes typically, and also is usually found at an edge. The shadows don't suggest that the camera was looking that closely into the sun anyway/

This looks to me like a seating problem with your back or bellows.

Steve M Hostetter
26-Feb-2011, 06:09
i think it's just careless withdraw or replace of the darkslide ,, we have all done it!

pinch the holder inside the spring back when you remove and replace the darkslide ..

this will keep the holder from moving around while you perform this task.

this is never a problem with the Hostilux :D

Bob McCarthy
26-Feb-2011, 07:16
I might guess a possibility. As you reinserted the dark slide, you added some back pressure, cracking the light seal just a touch to fog the exposed film. Dark slide partially inserted would cover film area to left (right side of camera).

The spring tension on some cameras is not stout enough to prevent heavy handling from the photographer.

What camera are you using?

Bob

Gem Singer
26-Feb-2011, 07:34
Now that the OP has revealed (see post#7) that this problem occurred with more than one film holder, it reduces (but does not eliminate) the possibility of lens flare or a faulty holder.

Since the leak is at the sides and not at the ends, it doesn't look like operator error while inserting or removing the film holder or dark slide.

If the camera has an interchangeable bellows, check to make sure that it is seated and fastened properly.

If the bellows is not interchangeable, and has no leaks, check the felt baffle in the camera surrounding the opening where the holder seats when it is inserted under the ground glass. A piece of felt could be missing preventing a light tight seal.

Gem Singer
26-Feb-2011, 07:38
Hey Bob,

We posted at the same time.

Thought you'd be out shooting this morning.:) :)

Bob McCarthy
26-Feb-2011, 07:43
I'm in lazy mode today. I'm typing this on ipad in bed. I may just stay here all day.

Zzzzzzz

B

GabrielSeri
26-Feb-2011, 12:38
i think it's just careless withdraw or replace of the darkslide ,, we have all done it!

pinch the holder inside the spring back when you remove and replace the darkslide ..

this will keep the holder from moving around while you perform this task.

this is never a problem with the Hostilux :D

I think this was my issue, I will find out tomorrow when I shoot/develop and test the back, bellows and holders for any problems.

Thanks again.

al olson
26-Feb-2011, 13:51
I think you have two problems here. The diagonal streak in the upper right looks like it has come through the holder flap.

The large vertical streak is strongest at the top suggesting that it came up through the bottom of the camera.

I had a similar problem for a couple of years after I had replaced the bellows and glued them in with Pliobond. I had applied good pressure and believed that I had a good seal. But I still had this nagging problem of a light leak that I couldn't place.

It was never a problem indoors and only an intermittent problem outdoors, even in strong sunlight. I did the flashlight test time after time, but it all looked good.

Not until I had some negatives with streaks indicating that the strength of the leak was coming from the bottom of the camera did I get a clue. I did the flashlight test once again and found light leaking out at the bottom where the bellows were attached to the back. It was not obvious from the other tests because the leak was inside the housing.

From the problem negatives and reconstructing the occasions where the leaks were a problem, it was usually in bright sunlight at times when the dark slide had been pulled during a longer wait, either for the light to change, or someone to get out of my way, or giving instructions to a model.

It turns out that Pliobond, while making a strong bonded seal, transmits light. I used some Brush-On Electrical Tape, recommended by someone on another thread, to cover over the Pliobond. So far everything has been working well.

With the flashlight test it can be easy to overlook a leak inside the housing because it is difficult to look in there. Not until I pulled the back out on the Technika was I able to see light coming out from around the bellows.

Andrew
26-Feb-2011, 16:15
looks like light leaks somewhere around where the film holder sits in the back of the camera.

There's the obvious big leak vertically across the frame left of centre but there's also smaller slanting leaks at both top corners. They suggest the film is in the holder and within the camera. I have a tachihara that I won't use anymore as it does this all the time because the back is defective.

There's a small mark at bottom left corner that must be unrelated... probably something in the darkroom like a hanging clip?

If you've had no leak in any other exposures it might be as simple as the film holder not being properly pushed into place in the film back on that shot. I've had that a few times with my linhof and speed graphic when I was being careless.

It could be an actual probem with the back that isn't showing up every time for one of any number of reasons.... like: whether you've got the sun directly on the camera, whether the holders have some play within the camera back and their position varies, how long you've had the dark slides out of the holder, whether you've left the dark cloth over the camera when the dark slides are out etc etc.

it's also possibly that one holder is a bit warped and that makes it more twitchy than the others and more prone to leak if there's any underlying issue with the camera back.

can I suggest you look very carefully at the camera back where the film holder seat and check for any warps etc. Then look at the holders for any warping. Then check for leaks around the back with your best holder in place same as checking for bellows leaks ie get in a darkened room with a torch. If there's any play in the holder wiggle it around a bit to see if there's some positions that open up a leak. If the back comes right off the camera that'll make it easier to check that mating area.

I did this with the Tachi and the rotten thing showed light leaking at multiple points around the back when the holders were in place and it varied as the holders moved around [and there was quite a bit of excessive play]

addit: I don't think I've managed to open up a light leak from pulling / replacing the dark slides as yet but I'm definitely aware of finding the holder being skew in the back and I'm sure it was never in the correct place to begin with.

MumbleyJoe
26-Feb-2011, 21:01
This reminds me of a problem I had had with my Tachihara, though I can't say I've 100% eliminated every last issue, but I think I found my major culprit.

This was hard for me to actually find, but looking into the camera with the film-holder in place, I noticed a couple spots where the glossy finish of the camera came through inside, where it should have been flat black.
http://www.tylerwestcott.com/temporary/tachihara3.JPG

That little strip of red paint was reflecting stray light onto the film, creating similar-looking flares. I bought some matte black paint from a craft store and painted over the gloss.... it mostly did the trick. It can't hurt, anyway.

EDIT: If nothing else, this is yet another way to trouble shoot your camera (looking in, towards the seated film-holder)

GabrielSeri
26-Feb-2011, 22:57
I found the culprit, metal screws in the inside of the bellows to the bellows frame. http://www.silverpiscis.com/Photography/5x7/IMG_8308.jpg

http://www.silverpiscis.com/Photography/5x7/IMG_8306.jpg

Andrew
27-Feb-2011, 00:10
but you seem to have had three distinct sources of light onto the film rather than just one so that doesn't quite explain the problem...

and the extra exposure is more than I'd expect to see from a simple internal reflection because you seem to have more than 1 extra stop exposure in places and I don't understand how you can more than double the exposure by reflecting the same light that's coming thru the lens. The physics strongly implies a seperate light source like a leak somewhere.

of course, there's still the observation that it's only the one frame you've had mucked up so it may be a transient problem from how the holder was mounted in the camera for that particular shot or some other handling factor like pulling the holder loose when you tug the dark slide. So, if you cover the screw head in black paint and never get another problem it doesn't mean that the screw head was the problem.

in passing I've also read people saying they've had light leaks thru the film holder's light trap when they tried leaving the dark slide partly inserted so it'd be easier to replace after the exposure [may not apply to you, of course]

Brian C. Miller
27-Feb-2011, 00:20
I don't think that it's the screws. If it were the screws, you'd see sort of a "halo" on the film, and certaintly not the main light leak. The bellows in that area looks like it's attached a bit flimsily. Send the camera to someone who does bellows work and get it attached properly, or at least get some matte black tape, and tape the area.