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rolee
18-Mar-2017, 10:58
Hello everybody,

I am new to large format, shooting 4x5 for a year now. I shoot mostly alpine landscapes and the results of my negatives are very inconsistent. Until now I thought the problem was uneven development of the negatives but more recently I started to think of light leaks.

So I tested my film holders today - and I recognized light leaks with all of my seven film holders (4x5 Fidelity Elite holders).
In a dark room I put a flashlight into the bellows of my Intrepid 4x5 camera, inserted a filmholder and pulled out the dark slide. I could see light through the felt of the dark slide slot (at a certain angle), and even more when the slide was still a bit inside and bent (see pictures).
162739
162740

It seems not much, however, when the film holder points towards the sun when taking a photograph it obviously is enough to cause film fogging.

I bought the film holders used from two different sellers and they looked very good and not much used. Is it possible that even quite new holders cause light leaks? What do you do to prevent light leaks? Cover the film holder using a dark cloth when taking the picture?

Thanks!
Roland

Leigh
18-Mar-2017, 11:28
Hi Roland, and welcome aboard.

I use a method with my dark cloth that might help.
It certainly could be used to confirm the diagnosis. I use it all the time.

When I set up the camera, I attach the dark cloth to the top of the camera with a pair of clothes pins.
When done using it, I fold it up on top of the camera so I can load a filmholder.
Then I drop it down over the back of the camera, so it totally shields the holder.

Even if you don't do this all the time, it's a simple and cheap way to test your evaluation.

- Leigh

Vaughn
18-Mar-2017, 11:43
I pull and insert darkslides under the darkcloth. A little tougher with 8x10 and 11x14, but it is a habit now.

Alan Gales
18-Mar-2017, 11:58
I bought the film holders used from two different sellers and they looked very good and not much used. Is it possible that even quite new holders cause light leaks?

Have you ever heard of Murphy's law? Yes, it is possible.

You could always buy new film holders but most of us (me included) buy used holders. I buy ones that look as new as possible and haven't had any problems.

I did once buy some well used 8x10 film holders cheap for a friend that ended up having light leaks. It was weird. They leaked part of the time but not all the time.

You could drape your dark cloth over the film holder. I drape mine over my bellows when making an exposure just as an added precaution. I'd still repair or replace the leaky film holders you have. I've never done it but some on here have replaced the tape joints.

Welcome to the forum!

Willie
18-Mar-2017, 12:23
The "Morley Baer wrap". You to all the focus, compose and insert the film holder and wrap the bellows & back with the dark cloth so light is blocked out. Baer used an 8x10 many would have gotten rid of for years. Has light leaks in the bellows so he would wrap it with the darkcloth.

Maris Rusis
18-Mar-2017, 14:27
If I face a situation where the sun will shine straight down the dark-slide slot I attach the ground-glass back to the camera upside down. The film holder goes in from beneath and when the dark-slide is pulled down the slot sees the ground not the sky. Then the focussing cloth is wrapped around as added light proofing. If the rear standard of the camera is a long way forward to work with a wide angle lens and I can't push the film holder in from below then the entire camera can be tilted over (carefully!) 90 degrees. Again the dark-slide slot can be arranged to see the ground and not raw sunlight.

Doremus Scudder
19-Mar-2017, 03:38
A light leak from the light trap of a film holder makes streaks on the film, usually closest to the opening. It is random and non-image exposure and looks nothing like inconsistent exposure or development. It would really help to see a photo/scan of the negative(s) in question. Just take a smart phone photo of it held up to your computer screen or open window.

Yes, you may see light through the light trap from your test, but we can't tell from the description of your problem that you actually have negatives damaged from such a light leak.

Some pointers for preventing such leaks around the light trap:

It helps to keep the time the darkslide is out to a minimum. Pull the slide, make the exposure, replace the slide. For those times when you have to wait a long time for things in the scene to settle down (wind motion, etc.), then do cover the darkslide opening with something.

I try to cover the holder with something even when the darkslide is out for short times. I work a lot without a dark cloth, so use other things a lot. For example, if it's not windy, I'll simply pull the darkslide and then hold it over the light trap (I can balance it on the holder and camera back for vertical shots). I also hang my hat/cap over the darkslide opening to block stray light, especially when I need the darkslide as a lens shade. For those times when I know the darkslide will be out a long time, I have made a small cardboard cover for the top of the holder out of the bottoms of old film boxes. It's a press fit and stays on even in strong wind. Of course, the darkcloth will work well too if you're using one.

I've used Maris' trick of re-orienting the camera back so that the darkslide opening doesn't face the sun as well a time or two.

However, maybe a light-trap leak is not your problem at all; let's see the negative.

Best,

Doremus

Pfsor
19-Mar-2017, 06:12
Rolee,
as you are new to LF photography, don't condemn yourself to years of working with defective film holders. Bellows, cameras, film holders are all conceived to work properly in daylight without need of covering them with dark clothes and hoping it will work!
I have never needed to cover my cameras or film holders with anything while enjoying taking pictures. At most I take care of not pushing the dark slide sideways when pulling it from the film holder.
If your film holder doesn't work as it should repair it or get new ones, properly working. Anything else is just giving up on the pleasure of taking pictures with correctly working equipment.
If you want to have years of satisfactory photography start with good working equipment first - it is well worth it! Just my 2 cents.

rolee
20-Mar-2017, 03:59
Hello and thanks everyone for your comments! Up to now I refused to take a dark cloth with me. This will change now! Also turning the filmback 180 towards the ground is a good idea, thankyou.
When analyzing my negatives I realized that they turn out ok when the camera is not in direct sunlight when taking a picture.

In reply to Doremus' post, here is an unmodified scan from a recent negative. It was shot in portrait orientation, with the dark slide towards the sky. The light streaks are obviously near the dark slide slot.

162806

I also made another test yesterday, loading my holders with paper instead of film and placing them in direct sunlight for 5 minutes (as paper is less sensitive). Then I developed the paper pieces.

162807

1 - negative paper control
2 - positive paper control
3 - holder in the camera, darkslide out, slot towards the sun
4 - holder in the camera, bending and pulling darkslide in and out several times, slot towards the sun
5 - holder in the camera, darkslide out, pulling the holder a little away from the camera for 2 sec
6 - holder alone in direct sunlight, different positions, for 15 minutes
7 - holder alone in direct sunlight, pulled darkslide a little for 2 secs
Darkslide slot is on the bottom of each piece. I did not test every holder for every situation. But according to the light leak test with the flashlight they all are about the same.

So for me it seems clear where the problem comes from in my case -according to pieces 3 and 4. It makes a difference how straight you pull out the slide, and if you are in direct sunlight or not.

Pfsor, as my holders where near to new (at least they looked like it) I am wondering if even new holders are completely free of light leaks - especially when having the camera in direct sunlight.

Pfsor
20-Mar-2017, 04:30
Pfsor, as my holders where near to new (at least they looked like it) I am wondering if even new holders are completely free of light leaks - especially when having the camera in direct sunlight.

Yes, film holders are conceived in such a way that if properly working they can be used in direct sunlight without the need of covering them with dark cloth.
By the way, I never use dark cloth, (too bulky for me) and I rather use a home made hood (made of paper) in the case the sun is shining on the gg.

Leigh
20-Mar-2017, 04:34
Yes, film holders are conceived in such a way that if properly working they can be used in direct sunlight
That's true of new filmholders.

But a filmholder is only new once.
As soon as you remove and replace the darkslide, the holder is no longer new.

Since you have to do that to load the holder in the first place...
NO holder in use is new, regardless of how long you've had it or how many times it's been used.

- Leigh

Pfsor
20-Mar-2017, 04:43
That's true of new filmholders.

But a filmholder is only new once.
As soon as you remove and replace the darkslide, the holder is no longer new.

Since you have to do that to load the holder in the first place...
NO holder in use is new, regardless of how long you've had it or how many times it's been used.

- Leigh

For you I will say it differently - film holders are conceived in such a way, that they can be used properly for many years even in direct sunlight. They are not auto-destructive once you have moved the dark slide. My Fidelity film holders have been working properly for some tens of years now. YMMV.

Leigh
20-Mar-2017, 04:49
My Fidelity film holders have been working properly for some tens of years now. YMMV.
So have mine, but that's a meaningless statement.

Anyone can go through life thinking that failures always happen to someone else, and nothing bad will ever happen.
That's just silly.

It's a difference in philosophy, based on your lack of understanding of reality.

When (not if) a failure occurs, I'll come home with good negatives. Yours will be ruined.

- Leigh

Pfsor
20-Mar-2017, 07:36
Have a good time with your film holders. I have a good time with mine. The end of philosophy.

Doremus Scudder
20-Mar-2017, 09:58
rolee,

Super tests. I'd add one more thing for you to be careful of. Often, one can pull the spring back with filmholder away from the seat in the camera back when removing the darkslide. Using the fingers and thumb of one hand to pinch the spring back and camera body together when pulling and re-inserting the darkslide will prevent this. Do check the filmholder seat for light leaks as well.

And yes, Pfsor is correct; properly working filmholders can be used without covering the opening with no problems. That said, I've ruined too many otherwise good negatives with light-trap light leaks with holders that (even afterwards) test just fine. For me, better safe than sorry; I keep the light-trap opening covered with something whenever practical. It's standard procedure for me to simply hold the darkslide over the opening for most shots. When I have to wait a longer time with the darkslide out, I'll use the darkcloth. When out in the field, where I usually wear a baseball cap of the like, I'll just hang my hat over the opening.

Re. darkcloths: They don't have to be heavy and bulky. One that I use often in Europe is simply a piece of white ripstop nylon and a thin piece of black sateen sewed together. I've got self-adhesive Velcro on the edges so I can close the opening under the camera and get things really dark. I weighs a few ounces. In the States, I have a larger white GoreTex and velveteen darkcloth. It is Superman-cape size, doubles as a rain poncho and reflector and still rolls up to a very small bundle that straps on the back of my pack. I carry it always even though I don't always use it.

Best,

Doremus

Martin Aislabie
20-Mar-2017, 10:35
I always keep the Darkslide Slot shaded when the Darkslide is out of the slot.

The easiest way I have found to do this, is to keep the camera with the sun on the other side.

Alternatively, I either use my head or body as a sun shade or just my hand to keep the slot in shadow as the darkslide is removed - and then use the darkslide as a flag to shade the slot during the actual shot.

I never use my darkcloth to cover the camera and/or film holder as a shade when taking the shot - there is far too much sail area - and an unexpected guest of wind (aren't they all) can/does blow the camera over.

Personally, I like the fact I have the darkslide in one hand as a press the shutter using the other - that way I know its not in the light path.

There are a couple of other things to watch out for :-

Firstly - is the film holder properly "home" in the back of the camera.
I sometimes find it tricky if I'm stretching to insert the film holder to know if the holder is well and truly locked in to position.
I have now taken to giving the film holdera good tug and wiggle to make sure its inserted properly.

Secondly - light leaks around the edges of the film aperture of darkslide/film holder.
Again, I try and shade the film holders with my body when I get them out of my camera bag.
When the film holders are in my camera bag, I always position the bag so the lid of the bag will act as a sun shade - or use something else hat/coat/darkcloth/.... to keep the film holders in the shade as much as possible.

Hope this helps

Martin

JMO
20-Mar-2017, 18:09
Rolee,
as you are new to LF photography, don't condemn yourself to years of working with defective film holders. Bellows, cameras, film holders are all conceived to work properly in daylight without need of covering them with dark clothes and hoping it will work!
I have never needed to cover my cameras or film holders with anything while enjoying taking pictures. At most I take care of not pushing the dark slide sideways when pulling it from the film holder.
If your film holder doesn't work as it should repair it or get new ones, properly working. Anything else is just giving up on the pleasure of taking pictures with correctly working equipment.
If you want to have years of satisfactory photography start with good working equipment first - it is well worth it! Just my 2 cents.

This is wise counsel. ...

Leigh
20-Mar-2017, 18:15
If you want to have years of satisfactory photography start with good working equipment first - it is well worth it!
I certainly agree with that.

I've also been doing this long enough to know that sometimes stuff happens.
A bit of effort expended to guarantee that a problem won't turn into a failure is cheap insurance.

- Leigh

John Kasaian
20-Mar-2017, 20:39
My leakers go into a cannibal box. Parts will be harvested to repair other film holders.
I won't sell a leaker--- it just ain't right!

Leigh
20-Mar-2017, 20:44
My leakers go into a cannibal box.
If I ever found one that was demonstrably leaking, it would migrate to the trash can instantly.

So far that hasn't happened.

But I've only been shooting LF for 57 years, so maybe I've been lucky.

- Leigh

Kirk Gittings
20-Mar-2017, 21:02
I don't think this is very complicated really. I only buy used holders and only use the ones that do not leak in direct sunlight. They are easy enough to test. I have about 40 good holders (4x5). Some I have been using for decades. The only ones I have had to retire were ones I did dumb shit with like dropping one from the roof of a 15 story building or dropping one in a stream (the film stuck so bad in the rails that I could never get the rails clean enough again).

Salmo22
24-Mar-2017, 20:26
I don't think this is very complicated really. I only buy used holders and only use the ones that do not leak in direct sunlight. They are easy enough to test. I have about 40 good holders (4x5). Some I have been using for decades. The only ones I have had to retire were ones I did dumb shit with like dropping one from the roof of a 15 story building or dropping one in a stream (the film stuck so bad in the rails that I could never get the rails clean enough again).

Kirk:

I recently inherited two dozen 4x5 film holders when my father passed away in August. As a general rule, he took very good care of his equipment, so I assume they are in good working order. That being said, what is the proper way for me to test these holders for light leaks? Thanks in advance.

Jeff

John Kasaian
25-Mar-2017, 07:39
The standard test is to load them with paper (cheaper than film) and leave them in sunlight for awhile---flip them over halfway through the ordeal to subject both sides to the sunlight---then develop the sheets and see what leaks are exposed.

Jim Noel
25-Mar-2017, 13:41
SInce my film holders are always under the protection of the dark cloth, or in the dark room I don't worry about light leaks. If I get a light leak it is because I was careless wile photographing.