I'm on day 16. I recently purchased a new flashlight - its rediculously bright - little thing, but it was expensive! I though I'd give it a try for candling. The light I used before was OK - but I really couldn't see inside the egg. Just the air cell etc. With this puppy - I was able to see the feet, head, beak, veins - it was crazy! I was able to tell I had 2 new duds - they hade developed pretty well & then gave up the ghost for some reason. In any case - I have 8 slightly sunburned chicks still kicking (literally - I could see it). Hopefully by Friday I'll have 'em all in the brooder.