How to tell if film holders are light-tight?

[Policar]

I have like ten old film holders (mostly fidelity) and I have no idea which are light tight. All I want is to find three good film holders. It's really frustrating! Many of them are in bad shape, some with tape that needs to be replaced.

Is there any way to test without wasting film?

This was on the edge of one of my chromes...what does that mean?

Thanks!

[Gem Singer]

The tape at the flap end has not directly related to the light tightness of a film holder.

It merely serves as a hinge for the light traps that are built into the plastic end flaps.

Light leakage in film holders is usually caused by worn out felt in the light traps.

Old worn out plastic holders are usually ready for the dumpster. The easiest way to determine their light fastness is to try them out in the sunshine. Waste a few sheets of less expensive B&W film.

Your picture shows a possible light leak. Can't tell which end it is leaking from without seeing the notch code.

[Jack Dahlgren]

I have like ten old film holders (mostly fidelity) and I have no idea which are light tight. All I want is to find three good film holders. It's really frustrating! Many of them are in bad shape, some with tape that needs to be replaced.

Is there any way to test without wasting film?

This was on the edge of one of my chromes...what does that mean?

Thanks!

Could just be a reflection off the holder - looks pretty small.

If you take your holders in a darkened room with a flashlight, pull the slides out and shine the light in through the slot you can see if light is leaking. I have some very old film holders that don't leak and some newer ones that do.

If you don't want to waste film, you can load them with photo paper and take them out in the sunlight for a while.

[Frank Petronio]

You can also live with minor leakage like that example... I would just load them and go myself, but when it comes time to track down the culprit - leaking holder - you need to take notes of what you shot with numbered holders - or better yet, file a tiny notch (or six...) in the edge of the folding flap so it shows on the margin of your exposed film.

[Ash]

you could use RC paper and load each holder, leave them in the sun for a while, then develop one by one... any leaks should be apparent

[Daniel_Buck]

you could use RC paper and load each holder, leave them in the sun for a while, then develop one by one... any leaks should be apparent

indeed, this is probably the best and most sure way. Some leaks may only be visible in bright light. sacrifice some paper or film, and make notes of what holder goes with each sheet.

[Policar]

Thanks all. I should have anticipated that figuring this out would be time-consuming, painstaking, and expensive--it's large format, after all. I'm going to try the flashlight method first to see if there are any obvious culprits.

I still have a minor panic attack about film flatness and light leaks every time I take a shot. And it's yet to be a problem, so far as I can tell. I'm just so not used to this.

[zcary]

I still have a minor panic attack about film flatness and light leaks every time I take a shot. And it's yet to be a problem, so far as I can tell. I'm just so not used to this.

I would think that the price of a few cheap sheets of b&w film or paper would be worth not feeling this panic everytime you shoot, and it could also help you from not ruining a important shot later on.

I think its important to be able to trust your gear.

[Vaughn]

Put the holder on a white piece of paper -- check it every once in a while to see if any darkness has leaked out onto the paper You might need to lift the holder up to make sure it is real filmholder darkness and not just a shadow cast by the holder onto the paper.

[Policar]

Put the holder on a white piece of paper -- check it every once in a while to see if any darkness has leaked out onto the paper You might need to lift the holder up to make sure it is real filmholder darkness and not just a shadow cast by the holder onto the paper.

Well....I thought it was a valid question.

[Frank Petronio]

I looked at your photo, it probably is some leaking felt in a light trap. So what? It's outside the crop isn't it?

I wouldn't be too nervous about film flatness or light-tight holders. It is rarely the problem that the internet makes it out to be, millions of sloppily handled large format films have been ham-handled successfully. I would just check that the holders look OK and run with it, and see if you have ever a problem before investing in solving a problem that doesn't exist.

Holders are so cheap now that you just toss a funky one and buy a few more. Why even use a holder that's suspect?

If it's an important shoot then you want tested equipment, but most of the time just shoot normally and watch what's happening.