You're elevation relative to the horizon matters alot in terms of when it gets dark. In a hollow it might be impossible to see 30min before or after, but on a tall ridge or mountain you might be able to shoot close to an hour before or after.
Also, I know with a really nice scope (for example I have a zeiss 3-9x40), you can practically shoot at night on a full or near full moon ... obviously irrelevant for bowhunting.
Just enjoy the time towards the end of shooting light that you get with a trad bow ... with a compound and a peep sight you get alot less time after sunrise since it acts liek a lens and cuts down on the light.
Hope that this doesn't qualify as unnacceptable conversation, since I'm only mentioning it as it relates to the question of shooting light and hunting hours.
Cheers