I just hatched eggs here for the first time. Ameraucana and cuckoo marans in the same batch with a few lighter brown eggs and a pink one. I went crazy trying to candle them, so overly worried about stink bombs. The led flashlight and 2 other portable lights in boxes that I used to check them initially were not bright enough by the 10th day! I used a heat lamp with a flood light and cardboard with a hole taped to it, but it was pretty hot! Then it fell and the bulb broke out of the socket! So much for showing the boys some progress! I need a more child friendly version next time.
What shocked me was that the green eggs were even harder to see through than the maran's. The EE's were so dark and grey, I got nothing but the air sac! The cuckoo maran eggs weren't so bad and I caught glimpses enough to see if it was good or not. No movement, but shadows were visible. The flood light helped me eliminate one more infertile and a blood ring that I hadn't caught with the flashlights. And the one egg my kids did get to see before it fell was really moving around, they thought it was the coolest!
I'll probably make my own for next time, put a nice wood box together for a stable stand. Maybe even a switch! Fancy!