Cool pictures! In my opinion, day 8 is too early to remove anything except eggs that are leaking or smelly. At this stage, developing eggs can look very different. You're still seeing a lot of shadow from the yolk. And depending on how the chick is positioned, each egg can look very different. I've had eggs where at day 18, the chick seemed to take up significantly less space in the egg. I figured they were developing slower, but then they hatch on day 20!
There's really only a few things you're looking for here:
-the air cell (you should candle from the air cell end btw). Is it getting bigger? Is it getting too big? Is it moving? ( shipped eggs) Sometimes with thinner eggs, I'll raise my humidity a touch because the air cell grows too fast. You'll pay more attention to air cells in another week or so. At day 8, it won't be very big. Also, air cells on shipped eggs can take on bizarre shapes, but they can still hatch.
-veins. Easier to see from the air cell side. May not be that obvious on day 8, especially in darker eggs
-blood rings. Sometimes thick veins can look like a blood ring. I always leave them in for a few more days to be sure.
- movement. For me, this is the easiest way to gauge the health of the egg. Even on dark eggs, by day 10 you'll be able, once your eyes adjust, to see a shadow shifting inside the egg. No movement can mean they're resting though. And later on when the egg gets crowded, they can barely move at all sometimes.
The more you candle and hatch, the better understanding you'll have of what you're seeing. Good luck!
A week to go! Weighing and candling tonight.
