Legally speaking, if you're doing any kind of "work" in the US, meaning pretty much anything that doesn't involve sitting around in meeting rooms, you're supposed to get a nonimmigrant work visa. This is the case regardless of who is paying you, and even if you aren't being paid at all (eg. internships). And as you've found out, getting one of these involves a world of pain.
All that said, practically speaking, as long as you keep your trips pretty short, odds are very high you'll be fine with a regular ESTA or B1/2 visa, just state your itinerary and that you're going there to travel, see the sights, etc. If quizzed about your video gear (highly unlikely, because the people quizzing you at immigration won't know about it!), state that you're a keen photo/videographer. All of this is perfectly true, and things may only get sticky if you're asked who is paying for all this and they don't take "I am" as an answer.
Yes, there is a small chance you'll run into trouble, be denied entry and need to apply for visas whenever you go to the US. However, a travel company I used for also did lots of video production in the US, and AFAIK they both used VWP/B1/B2 and never had any issues. YMMV.