High power help!!!

I have a Tec 140 with a DenkII. I am looking for a bit of advice with eyepieces. I've had my beasty up to 294X on a good night with Tak 7.5 le's, but the next step with power was way too much around 500X. In the Northeast(PA) what do you think is the maximum useful power? At 294 everthing was crisp! Should I be happy here(never). Once I figure out a target, then I can choose another eyepiece set to get the max. I know the nights that allow this are few and far between, but I don't pass any of them up. Thanks for your help!
Mike

Mike,

I may get some argument from Mark, who has owned a TEC140, but I would say save your money and enjoy the view at 294x. As good as the 140 is, I just doubt that there is much to be gained by going from 300x to 400x. Your own statement that 500x was "way too much" would seem to confirm this.

I will also add to Mark's reply that at <0.5mm exit pupil eye alignment is critical in the bino, particularly when your own entrance pupil is stopped down by a bright object. I would recommend periodically closing one eye at a time to ensure that you are actually catching both exit pupils.

Enjoy, Milt