The Brinsea company’s incubation instructions are very informative on every aspect of the incubation process.  Following are some of the things I learned.

The egg needs to lose between 13% to 15% between the time of laying and pipping.

There are two guides that help indicate correct humidity:

1. The air cell increases as incubation proceeds.  To see this you should candle the eggs.
2. The other indicator is weight loss.

There are two controllable factors that influence humidity:

1. The amount of water surface area.
2. The amount of fresh air that that the incubator draws in.