LED red/amber bulbs for safelights?

[imush]

I am setting up a new darkroom, or rather getting things together for a makeshift one in a bathroom. I see that people successfully use red and amber LED bulbs instead of filtered safelights.
Theoretically, LEDs should be better with their narrow spectrum, and I would prefer not to have bulky equipment.

Anybody has current recommendations? There are plenty of cheap red LED bulbs for decorative lighting, but I am not sure about the wavelength. I know OptiLED red and amber reportedly work well, but these among the most expensive. Other manufacturers do not specify their colors.

 

[nikon_sam]

They do make and sell red or amber lamps specifically for darkroom purposes (used in normal light socket fixtures) and they do have recommendations for how close you can place these lamps to your working space or photo paper...
Using other light sources would require testing on your part to check for possible fogging of your photo paper...
I wouldn't use any lamps not designed for a darkroom but that's just me...

 

[sevo]

One thing to watch out for is that current high-power LEDs essentially emit deep blue, other colours are created with fluorescent dyes on top of a blue LED. Whether these are safe or not will depend on the type and efficiency of the dyes. They could show long term drift or suffer dye fading, and I'd always combine them with a additional safelight filter.

Old mid to low power LEDs directly emitted yellow, orange or red, in many cases almost single-wavelength, and as their physics does not permit them to alter their colour, ever, these can be used bare if the manufacturer specifies that they emit no blue.

 

[PKR]

Test your LED lamps with a sheet of printing paper at a decent working distance. Process and see if the paper is fogged. You should do this with common (incandescent bulb) safe lights too, as the filtering can fade with age.

 

[MartinP]

There are many discussions of this sort of thing over in APUG. For example, this thread. I'd say the simplest solution for setting-up time and for known effectiveness is a red bulb, designed as a safelight, placed in a desk-lamp and pointed at the ceiling. They are less than ideal for a very large darkroom, but for a bathroom sized one they are ideal. I used the equivalent european product for years 🙂

 

[elmonsanto]

red led bulbs

red led bulbs

I've had good results with these red led bulbs:

http://www.superbrightleds.com/cgi-...ge&category=MR16&Page2Disp=/specs/E27-W24.htm

The led bulbs supposedly emit light in a very narrow frequency range according to the spectral graphs for each color bulb. Check out the one for red.

I have two of the wide-angle red bulbs pointing up at the ceiling in my darkroom. I ran a bunch of tests, including leaving an unexposed sheet of paper emulsion-side up for twenty minutes. When I developed it, it was still paper white. YMMV so make sure to run the tests yourself.

Hope this helps

 

[xwhatsit]

I bought 100 red high-brightness (well, 20mA) 5mm LEDs (thrown in were 200 current-limiting resistors, 100 for 5V and 100 for 12V) off a Chinese eBay seller for $1 or $2, with free shipping.

After waiting a month or so for them to arrive, I then spent an afternoon soldering them up with some copper wire into a big LED matrix. Powered them with an old 12V power adapter and away I went.

Of course, a bit more labour intensive than just buying a bulb. And 90 or so 20mA red LEDs can be a bit headache-inducing after an hour or two in the darkroom! Really need a defuser or something for it.