PDA

View Full Version : Green safelights



David R Munson
21-Aug-2001, 00:35
OK, so once I sort out the film drying thing I posted about below, I intend to s tart developing my 8x10 stuff by inspection. This, of course, necessitates a gr een safelight. I was at B&H's web site tonight looking around and it appears th at the only green safelight filter available is the Kodak, which is only readily available in one of the 3 sizes offered. The fiter itself, 5.5" dia., is about $27.00. Factor in the cost of the proper safelight, etc, and it's not exactly a cheap thing. My quesetion is this- are there any other green safelights avaia ble? Perhaps some old/used options? I had thought about building my own using the correct filter and some sort of light-tight enclosure, but haven't gone much past the initial thought. Also, does anybody know where one can find an approp riate momentary on/off foot switch for use with a safelight? Thanks in advance.

Dave Mueller
21-Aug-2001, 10:35
I built my amber safelight by finding an LED module that had the same wavelength as the Kodak OC filter. A cheap 12VDC supply, three resistors and 72 LEDs later...Total cost was about $40. I built it into an old bathroom ceiling light fixture with frosted glass.

Dave Mueller
21-Aug-2001, 10:48
I found the vendor's link for the LED modules. www.lumex.com. Search for LXC1283. They have two green modules, one is 565nM and is a close match to the Kodak #7B (550nM). The other is a 525nM, and is a close match to the #3 filter. From comparing the Kodak charts to the modules I used (590nM), the #3 filter is very dark. The Lumex 565nM is super bright. You'll need to drop the voltage way down or put some ND filters over it. The 525nM is also bright, but nowhere near the other one.

My safelight is controlled by my timer (an old Radio Shack Model 100 laptop). I've seen foot switches somewhere, but can't remember who sells them. Check with DigiKey, since you'll have to buy the LED module from them anyways.

Jeff Buckels
21-Aug-2001, 11:53
Just get the Kodak deep green. Gonna be less trouble than any other option. As far as a switch, the footswitch is obviously the best thing, but a cheap pretty okay easy option is to just get a household buffer bar thingy from Walgreen's for a few bucks and attach it in a handy spot (mine's mounted opposite my belly button on the side of my wooden sink w/ a dot of phosphorescent tape on the switch button).... -jb

kthompson
21-Aug-2001, 14:20
For the inspection light over the fix tray (15w) in my darkroom, I just use a christmas tree light footswitch mounted on the side of the sink frame. I can just hit it with my knee more or less, to turn it on & off....I paid less than $10 for it.

Chris Ellinger
21-Aug-2001, 14:51
Modern panchromatic films are sensitive to all wavelengths of visible light. Green filters are used for inspecting film because the eye is most sensitive to green light, NOT because the film is less sensitive to green. So, a green LED could be used as well as a green safelight filter, since the LED wavelength of 565nm is approximately the peak sensitivity of the dark adapted eye. You will want to use the minimum intensity for the minimum length of time necessary to inspect the film.

Doug Paramore
21-Aug-2001, 16:23
Dave: For the footswitch, check your local sewing machine repair center for a switch, or maybe an office supply for a transcribing machine foot switch. You can make one easy enough by going to Radio Shach and getting a "momentary on" switch and wiring it to the light. As for the green safelight, try a clear class with a couple of layers of green cellophane and a small bulb. Good luck with your new quarter at the university.

Regards,

David R Munson
21-Aug-2001, 21:04
Lots of good information- thanks all!

Scott Walton
22-Aug-2001, 14:31
Dave, go to www.unblinkingeye.com. There is some good info on this and developing by inspection. I have done it with TMX but I prefer the older emulsions over the new! Cheers, Scott

Paul Giblin
27-Oct-2001, 07:41
Hi,

Does anyone know of a source for a Kodak #3 dark green safelight filter (or the Ilford equivalent).

Thanks, Paul