Quote Originally Posted by bdial View Post
There was some discussion some time ago on using CFL's. As I recall the method most used was to keep the light on all the time, and control the exposure with the lens cap or a shutter.
I have a couple of LED bulbs that look like they could work in an enlarger, they have a pretty dense white plastic dome over the LEDs. Haven't tried it for that, however, as my enlarger doesn't have a screw base lamp.
Yes, what we did with "cold lights" a long time ago.

Take care that whatever you use, it puts out light of the correct color temperature for the paper in use. LED I have seen are very blue, ok for graded paper or to get max contrast ONLY on VC. For low contrast on VC, you will need 2800 K wave lengths, ie yellow, to be available.

There may be warm LED available now. Go to Home Depot and check out their display.

Like to add fluorescents are spiky in spectrum and not continuous so there could be missing wave lengths that you need. Split grade printing might be the answer.