When to start turning the chicks light off at night

[Cathintheuk]

If you are using a hen to hatch your eggs ., go for a good broody type .... my choices are a Peking.

 

[Cathintheuk]

Or an Orpington.

 

[50-45-1]

Then as the sun goes down, and the room slowly becomes darker, they will adjust better to that right?

It's normal. Prepared for the loud cheeping however, as it will be their first time and strange for them. Just let them settle on their own.
It is best in the long run to let your chickens as adults, have natural darkness. They need sleep and rest just like us and constant light disrupts that.

 

[Crazy Camp]

I would start by putting a red light bulb on them at night, so they still have a little light. I've heard that chicks will completely freak out in the dark, I don't know when that changes.

My chicks have been just fine. when I turn off the lights for bedtime They are very quiet and content. They are two weeks old brooding inside house