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Marko Trebusak
10-Jun-2013, 06:39
OK, I know it sound stupid, but are IR googles safe for near IR films like Rollei IR? I searched quite a bit and by specification AGFA Aviphot's sensitivity drops to zero at around 770nm. Since IR LEDs emit at either 850, 860 or 930nm; there could teoretically be enough space between their emitting spectra and film's sensitivity spectra to work together? The problem might be with 850nm LEDs and 960 might just work with short peeks. So here is another question: are generation I IR googles usable with 930nm LEDs? Or is some kind soul with IR set up prepared to test my film?

Cheers,
Marko

Bill Burk
10-Jun-2013, 09:55
Hi Marko,

I have "looked at" IR LED's with my Generation 1 ATN-Viper. The LED is visible, I can see it light up when I connect the battery, but the light from the LED doesn't "illuminate" the scene. The goggles won't operate with light sources that are deep into IR...

The stock "almost visible" LED, which doesn't fog my usual film TMY-2, would most certainly fog a near-infrared sensitive film.

Marko Trebusak
10-Jun-2013, 13:34
Hi Bill,

Are you talking about 930nm LEDs? That's unfortunatelly what was expected. Another option might be 860nm LEDs. Their emiting spectrum is very narrow indeed. And if people are using green light for developing by inspection for panchromatic film, this might work right??? I seems to remember that Michael Kadillak developed Fuji Acros with IR googles, and that Acros suppose to be sensytive to IR light. But my memory is not something to relly on :rolleyes:.

Marko

Jody_S
10-Jun-2013, 18:15
Perhaps the graph here (http://www.digitaltruth.com/products/product_tests/infrared_film_010.php)will help. You should be ok with 850nm light source for everything but Kodak HIE. Obviously you will need the specs for whatever goggles you want to use, to know if the light will be visible.

Marko Trebusak
10-Jun-2013, 21:08
Hi Jody,

Thank you. Here is a sensityvity spectrum of AGFA Aviphot 200. It's also clear above 800nm. Now to the question: did anyone tested their IR googles for 850 or 860nm LEDs?
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