Go to this site http://www.minkhollow.ca/HatchingProgram/Candling/index.html they have really great candling photos of ducks. Good luck. Mine have only been in the bator a couple of days. I'm really going to be good and only candle on Sundays (if i tell myself that enough times, I may follow through) since they're Muscovy eggs and take five weeks anyway. I know I have a Muscovy drake, but I've never seen him fertilizing the eggs, but he may just wait until night fall and do it all stealthy-like. lol