I believe that the answer is no for casual tourists. If you are a serious exporter you can register for a State Sales Tax Exemption Certificate. I think the threshold is 5 camcorders at a time, so you are just below the limit

Also, given the aggravation you get at JFK duty free about collecting stuff you have bought, it's unlikely under any circumstances that you would be able to flash your passport in Manhattan, pay no tax, and walk away with the swag.

Regards

Mark