I use a modified flashlight also — not sure of the lumens. Not strong enough for very dark eggs, but that’s rarely an issue for me.I have a question for hatchers who candle. What kind of candler do you use?
I use a flashlight with 600+ lumens and the lens removed so the egg fits down in the bezel. Since most of my eggs are dark, I don't candle often and therefor a candler wasn't ever a priority but I may invest in one.