What is the optimal humidity and temp for seedlings?

What is the optimal humidity and temp for seedlings?

50-60wile in vege then as low as you can get it for flowering under 30

Cool thanks for the info...should the temp be around 74 as it would be throughout the veg and flowering or should it be a bit warmer?

good it helps if during dark time it drop about ten degrees.....

Cool thank you much