While both can be good, it would be evening where I hunt. In the morning the deer are headed back into the river breaks where they spend the day. They are done feeding and it does not take much to put them on the run. Then they are gone for the day and your done. There is no chasing them around the river break. If I had a stand and was in it before dawn then moring would maybe be ok. However in the evening they are comming up to feed and thats whats mostly on thier minds. Not very spooky then.