What should the humidity reading be?

[Fortheloveofchickens]

I need to know what the humidity reading should be at incubation and then at hatching. Do I follow the manufacturers instructions on my Sportsman 1202 Cabinet Incubator which says wet bulb temperature reading should be 82 to 86 during incubation and 88 to 90 during hatching? Or do I follow what I read on this site, 50 during incubation and 70 to 80 during hatching?
I have a digital thermoter/ hydrometer, not a wet bulb type. Is there a differnce in the readings between the two?

 

[SundownWaterfowl]

40% during incubation, and 65% during the hatch. I dont pay attention to the humidity the first 18 days. I dont even add any water. The humidity of the room that the incubator is in is around 50%.

 

[4-H chicken mom]

from Ohio. I keep mine at 50-55% and 65-70%. This is not wet bulb readings though. This is for chicken egg, duck eggs are different.