I was scrounging around in the basement of a local camera store and found a safelight with green glass. What is the green used for?
He also had a bunch of new in the box nikkor enlarging lenses 50mm and 80mm. Maybe others, but I didn't go through everything. If thats something anybody is interested in, he's selling the basement stuff off cheap. so far he's charging me about 10% of what is on the price tags.
A green glass safelight was (is) used to develop film 'by inspection.' When film is partially, but not fully developed, it is safe to look at the film under the green light for a short time during the development stage to judge how much more or less time is needed to make a proper negative. I have never done this but I believe at one time it was standard prceedure, particularly in newspaper darkrooms where there might be gross errors in exposure. Art photographers also put it to good use.. Robbie
http://robbiebedell.photoshelter.com
I develop by inspection for my sheet film with a green safelight and foot peddle to flash it briefly for peeks. There are also a couple other methods- one involves a desensitization dye and another uses IR goggles.
Under a green light at least, each film and developer combination looks a bit different- but its a nice technique if you don't love calibration and consistency but want relatively fool-proof negatives. Expose for the shadows and develop for the highlight density you know you want based upon a prior inspection test with film and developer at a known time/temp. If you peek through the base, instead of just looking at the reflected blooms of highlights on the base side which is typically how its done- you can also sometimes judge mid-tone detail and moderate agitation for desired highlight compensation relative to zones 5-6.
Yes, to develop by inspection.The only way I develop all of my large sheets of film. Only way to do it.
You can use a red light for dbi too by the way.
No, I think you are mis-informed. A Wratten #2 deep red is for Orthochromatic film. A red safelight will fog pan film, because it is sensitive to red. Ortho film is not sensitive to red. The green safelight is used for panchro film...very sparingly, and way late in the developement regimen. Assuming you are using something like d-76 developer, develope in the dark for about 80% of the cookbook time. Pull the sheet of film out of the developer, flash on the green light for a very few seconds, cut the light and put the sheet back in the developer. Give it another minte or two, and do it again. When the front and back sides look even, it's developed. By the way, keep that green safelight at least 4 feet away from the film. After you've developed a couple of sheets this way, it'll seem easy. So do your test shots and develop those this way till you get the glitches out of the procedure.
What do you mean, that a green safelight is the only way to develop panchromatic film by inspection (which I agree with) or that development by inspection is the only way to develop film? It clearly isn't that. Some people find it valuable, agreed, but many others including some fine and famous photographers concluded it was more trouble than it's worth. I haven't tried it and feel no need to. Standardizing time and temperature and exposing accordingly work fine for me.Originally Posted by Jim Fitzgerald
A green safelight is used because that is the frequency at which the human eye is most sensitive to light. Nothing to do with the film. Since the human eye has peak sensitivity in the green region of the spectrum, you can use comparatively small amounts of light and lessen the chances of fogging the film. The use of a desensitizer of tanning developers that serve the function of desensitization further lowers the risks. Cheers, DJ
Exactly. Film is sensitive to all light. Duh. Green or red.
When some of my fingers became insensitive due to a shop accident I got infrared goggles. The same is used by major film makers.
DUH!
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