All of the above is true but the "bullseye" may not be so easy to see for somoen that is not used to looking at eggs daily, egg after egg, some if you catch them within an hour of being laid will not look like they will say 2 to 3 hours after.
I candle all eggs as I collect them, and mark them, then I go back several more times over 48 hours to see if Im sure of what Im seeing. Heck with glasses, poor room lighting and a crappie flashlight I could have thrown out a lot of good eggs.
So even if I am 100% SURE they are INFERTILE when I collect them, I still incubate them and continue to check them until they, mold, or otherwise go bad.
I hatched my best babies in 2005 from "infertile, molded eggs" so go figure!
I do not see the need to candle eggs at all to tell you the truth... But if you must candle eggs, I think the way that Felicia illustrated is a good way to do it... The eggs are not being disturbed much that way...
After hatching a bunch of eggs, you will be able to tell in a few days if they are likely to hatch or not without candling... This comes with experience, but does not take long before you get the idea... Although, this is not 100% but neither is candling... It is a good idea to just keep the eggs incubating until you know for sure it is not going to hatch....
I agree with Wendy the bulls eye isn't always there, when finding the egg quickly after laying.
I always candle my eggs, but my reason is so that if I have an egg that looks infertile I will move it to another container. This way if it goes bad, it's not near good eggs and I don't risk mold spreading.
Thanks Gregg I like my way too, over using the other method for the same reasons, but also because it's fast, to skim right over all the eggs in one container real quick.
I candled both of my eggs last night and both have bullseyes
One is on the bottem of one egg and one is on the top. I have not turned them in any way, they are laying just as I found them.