What should eggs look like?

[Rose66]

What should a good fertilized egg look like when you candle them if they have not yet been put in the incubator yet? I received some turkey eggs through the mail yesterday and before I put them in the incubator I candled them to check for detached air sacs only to realize that I don't know what they should look like. lol Should I be able to see an air sac or not? Should I see something else or what?

Thanks,
Rose

 

[Louieandthecrew]

The egg should be completely dark and not see through except for an air sac in the top (almost) half of the egg.

 

[Rose66]

The egg should be completely dark and not see through except for an air sac in the top (almost) half of the egg.

I thought the egg didn't get completely dark until the chick was pretty much fully formed and therefore taking up most of the egg????