I have led computer fans that I use to keep a consistent temperature in the deep freezer. They were reasonably dim but I didn't know if since they run 24/7 it might skunk my beer in the glass carboy. Any help will be greatly appreciated.
Interesting question. There's plenty of data wrt wavelengths vs hop thiols reaction leading to that distinctive Heineken flavor (ugh), and iirc the threshold starts in the visible blue spectrum and then towards UV.
Intensity probably matters as it's all energy relative, but on balance and as one who tries to eliminate anything that isn't clearly a positive influence wrt to my beer, I'd try to eliminate any light source, period, in a fermentation chamber...
Quite some time ago, I read an article comparing the effects on beer of incandescent light bulbs vs LED light bulbs. At the time, I was feeling quite full of myself for having converted my place over to LEDs and I was comprehensively bummed to discover that LEDs were deemed to be not terribly good for beer.
LED technology has progressed significantly since then, but I'm having a hard time thinking that unleashing four eyeball barbecues in your chamber is hunky dory.
You could take a black garbage bag, poke a hole in the center of the bottom, and put it (upside down) over your carboy, with your airlock sticking through the hole. Then the beer is also protected from your room lighting when you open the freezer.
Thank yall for the responses. I risked it and just clipped the wires to the leds on each corner of each fan. The fans stayed running so it must have been wires such that the fan is separate. It's not quite as easy to see down in the freezer now but the new plan is to wire up a momentary switch to sit below the freezer lid that will activate on opening. Wish me luck I'll post results. - cheers