I recently had an educational encounter with the NYS Department of Taxation and Finance that might benefit others.
Background:
I have a Certificate of Authority to Collect Sales Tax in New York. That means that I can collect sales tax and pass it on to New York State Dept. of Taxation and Finance and am exempt from paying sales tax on photographic supplies. Material that I buy that is used in the production of the products I sell are exempt from sales tax, because sales tax only has to be paid once.