Texas tax law refers to tangible personal property and taxable services as taxable items.
Please refer to the publication 96-259 Taxable Services - http://www.window.state.tx.us/taxinfo/taxpubs/tx96_259.html - the photo services are not listed among taxable services and assumed non-taxable.
According to RULE §3.312 Graphic Arts or Related Occupations; Miscellaneous Activities - http://info.sos.state.tx.us/pls/pub/readtac$ext.TacPage?sl=R&app=9&p_dir=&p_rloc=&p_tloc=&p_ploc=&pg=1&p_tac=&ti=34&pt=1&ch=3&rl=312
(1) Photographers, commercial artists, portrait painters, and persons who draw, paint, engrave, and etch are graphic artists.
(4) Persons who furnish their own supplies in pursuit of their work including photographers, commercial artists, portrait painters, etc., shall pay a tax on their supplies, equipment, and any other taxable items used by them. However, when supplies or materials will become an ingredient or component part of a finished product held for sale, the materials are not subject to tax at the time of purchase by the artist.
So far, you should pay sales tax on all suppy, equipment, etc, but should not charge customers with sales tax.