LED darkroom bulbs?

[John Layton]

The cheap "amber" (Delta brand, I think) globe safelights which I'm currently using are actually a bit on the red side of amber - and so far, so good...at least with Ilford papers.

[Fragomeni]

Thanks all. This is the one I decided on.

Amazon link

It’s a 1 watt red led in standard socket size designed to replace ~7 watt bulbs. Most others that I found were 60 watt bulbs which seems far to bright. This one looks identical in brightness to any standard low watt darkroom bulb. I haven’t tested it yet but will soon and it seems promising.

[Edward Pierce]

I recently switched to using the S11 bulbs from superbrightleds. They’re very bright. I bounce them off the ceiling, which is white and rather low. First I tested two amber bulbs with Ilford MGFB Classic and got fog after 4 minutes. Switched to a pair of red ones; no fog after 7 minutes.

Then I tested the two red bulbs with Foma 111; fog after 1 minute. Now have to rig up a way to tone them down and test again.

[Ulophot]

Edward, in other posts I indicated my results with Ilford WTF and Fomatone. Foma seems more prone to fogging than Ilford, though I did not have the problem with the reds' I just don't like them. I tested the amber as safe but had to cut the output considerably. Not ideal, but if you can wait to see the print in the fixer and wash for making judgements, you may find it workable. It's takes a bit longer for eyes to adjust to teh lower light level, but once accustomed, mine seem to be ready to "open up" again when the inspection light goes off for the next print. Good luck!

[Tin Can]

Amazon now has a variety I have not tested yet

1 watt led light bulb red E26

[koraks]

Then I tested the two red bulbs with Foma 111; fog after 1 minute. Now have to rig up a way to tone them down and test again.

Try covering the bulbs with rubylith. Two layers generally does the trick. This cuts all but the red light, and dims the red light less than you'd have to do to get safe levels without the additional filtering. In other words, with the additional filtering you'll have much more (red) light to work with, which is very convenient indeed.

[ethics_gradient]

Typical LED's output a very narrow part of the light spectrum (in this case, the red bit that most darkroom papers aren't sensitive to) compared to a traditional bulb. I've been using cheap LED strip lights in my wet plate darkbox with no issues.

As other have said, definitely run tests before commiting to larger runs/prints.

[koraks]

Sure, leds have a narrow spectrum. But they also have secondary emissions outside their primary spectrum. That's where the problems stem from. Take your cheap strips and view their light reflected on the surface of a cd/DVD. I bet you'll see a nice rainbow that also shows some green and even blue which shouldn't be there if reality was as simple as the "narrow spectrum" statement suggests.

[ethics_gradient]

My unfogged plates suggest that it doesn't matter for my application. Hence, my suggestion to test.

[koraks]

Well, wet plate is extremely slow and has negligible sensitivity to green light, so pretty much any kind of red or yellow light would be ok for it. Paper is a whole different matter, and fast ortho film is yet another step up.