Week 2 Update Chicken Eggs in Incubator

Keeping the humidity between 45-55% during incubation, will lock them down and keep between 55-65% humidity. Today, I'm on day 15 (not the day this video was made), and I have 12 great looking developing eggs in the incubator. The others did not develop much or embryos died. I suspect my thermometer was not accurate and it was too hot inside the incubator. I'm trying to figure it out.