low humidity

Hi there, I am on Day 28 with my 6 eggs, and see and hear nothing yet. We miscalculated by a day so the eggs went into lockdown a day later than they should have (Day 26) - so we didn't candle them as I didn't want to disturb them. Prior to that, all were moving and seemed to be growing fine on...

So its our first time hatching quails and lockdown started on monday, last night 11pm GMT we had noticed some pipping & zipping from one of the eggs and can see clear movement. However it turns out that our hygrometer was displaying an incorrect humidity and on further inspection it looks like...

I know that if you incubate at too high a humidity that they can drown in the shell, but what happens if it's too low? I live in a very dry climate where the humidity is often down to 15% (I add water to my bator so it's higher in there!!) so I was wondering what I would see doing eggtopsies...