Red theatrical gel for safe torch / flashlight?

Xícara

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Hello,

I'd like to have a hand-held safe-light to help me develop photographic paper and x-ray negatives by inspection. Would a red theatrical gel wrapped around the business-end of a torch/flashlight do the trick?

Thanks
 

pentaxuser

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I haven't tried theatrical gel but the answer is: it probably depends on whether it matches the kind of safety filter red that is used on an enlarger or in stuff called rubylith

All you could do would be to test it unless you can say who makes the gel and find out if anyone else has used it with success

Electric fires used to use red bulbs which rotated to give a flames effect under a plastic surround that resembled a coal fire but I very much doubt if they were darkroom safe

pentaxuser
 
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Xícara

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Thanks @pentaxuser - I'd most likely use Rosco gels as they have an office here. Their "Supegel #27" (medium red) looks like it might be a contender. It's the darkest red they stock and I can always use multiple sheets over the torch if I need a dimmer light.
 

koraks

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Ah, that's a pity. Well, give the gels a try; maybe it'll work. However, having done x-ray development on inspection many, many times, I found that only two layers of rubylith over a rather dim red LED bulb worked well.
 

grain elevator

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In this day and age, I think red LEDs plus, if necessary, filtration is the way to go. My darkroom safelight is a chain of red LEDs. It's good enough. Perhaps a red flashlight is enough for what you need? I'd try that first and add whatever red filter you can get second, and try again. I safelight test is trivial.
 
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Xícara

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grain elevator said:
Perhaps a red flashlight is enough for what you need?
Click to expand...

Yes, it's tempting. This head-mounted lantern is cheap and has a switch on the underside of the bib, so I could use it as sparingly as possible.

Fixpel - Lanterna de Cabeça Fixlumen Luz Led Vermelha

Lanterna de cabeça indispensável para aplicações profissionais em situações de baixa ou nenhuma luminosidade nas quais não é permitido o uso de luz branca. Produto nacional patenteado prático, durável, resistente, leve e confortável, útil e eficiente.
www.fixpel.com.br

I'll look into doing a test. I don't actually need a portable lamp for normal printing, but I'll soon be trying lith printing with Ansco 70 and some ancient Kodak Polymax II RC paper. I'll do a test with that and with the x-ray film I use.
 

Molli

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Xícara said:
Thanks everyone. Can't find Rubylith here, but I'll keep looking. I use Ilford papers.
Click to expand...

Would an A5 size piece of Rubylith suffice? I have an A4 sheet left, but only need half of that to cover my mobile phone screen. You're welcome to the other half (A5 ≈ 140mm x 210mm). It's quite thin, but it is the correct wavelength.
I know what it's like trying to find this and copping huge postage bills.
If you're comfortable with doing so, PM me your address and I'll pop it in an envelope for you. I've sent some to other people online here if you need someone to vouch for me. I don't know what the travel time will be between Australia and Brazil, but I'm sure it will get to you eventually. ☺
 

MattKing

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You cannot tell by looking at filter material or a light source whether it also transmits appreciable amounts of the green and blue light that will fog most papers.
Light reflecting at an angle off the surface of a CD or DVD can sometimes reveal if there are blue and green components of transmitted light.
 

Nicholas Lindan

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Rosco publishes the transmission spectral curves of their filters and they are in their filter sample book (highly recommended). The #27 transmits nothing below 580nm.

If you start with a red led you are most of the way there.

There are dimmable filtered LED flashlights made for the amateur astronomy crowd. I have used a Celestron unit for some years - but only with ortho film & paper materials so I can't speak to their use with x-ray film.
 

BobUK

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I once fitted a scratched red lens filter into a torch. Luckily it worked as a safelight until I dropped it and the glass broke.
 

pentaxuser

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BobUK said:
I once fitted a scratched red lens filter into a torch. Luckily it worked as a safelight until I dropped it and the glass broke.
Click to expand...

Yes any enlarger safety filter that is surplus to requirements and can be cut to the same size as the torch glass front has to be one of the best solutions

pentaxuser
 

ic-racer

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I use a disc of Roscoe Primary Red behind the protective clear plastic on my darkroom flashlight.
 
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Xícara

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Thanks for the kind offer @Molli . At this point point I'll probably go the red LED route and experiment with gels. But if that fails I'll be in touch!

@bernard_L , thanks, that's great know. The Lee primary red is available here. It has the code #106. Rosco also has a Primary Red with the same code.

@Nicholas Lindan - yes, the head-worn device above is meant for amateur astronomers and night hunters/naturalists but doesn't have a dimmer. I'll look further. Which do you think would be better to use, the #106 or the #27 gels? The 27 lets through very little light I read - but perhaps that's the right thing.

Cheers

edit: @ic-racer - great!
 
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eli griggs

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My early Maglight, two AA battery flashlight gave many years of darkroom service with a couple of layers of Rubylith, and I might even have the, now, three decades old sheets I cut back in the afterlife, with my darkroom files and books.

This was before maglight LED bulbs though, so if anyone knows different, please, speak up.
 

Michel Hardy-Vallée

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I've seen people use Rosco E106 gels for that specific purpose.
 
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