Scouting..

[Ambuscher]

As far as I'm concerned any time you can get into the woods is the best time to go. I don't call at all unless I'm there towards the end of the day just to hear one gobble on the roost. It's not a good idea to call early like your hunting. One you don't want them to get too used to your calls, and two, if your like myself its hard not to go ahead and call them in and take a pic or two. LOL Need to save that for the hunt.

[Covehnter]

The best time to go would be at first light b/c thats when the turkeys are most vocal and you can pinpoint where they are roosting. Afterwards you can walk around looking for scratchings, droppings, dust bowls, etc.