Bad photocell? Or does this run off a switch? (or is it a thermal PC that hasn't had its 30-second time delay?) Very nice light. What did you use for an arm? Is it custom?

Thermal PC. Snapped the image before it cycled off. I make most of my own bracket arms since most of the lumes are affixed to flat surfaces. Plus we get wind gusts around here up to 70 MPH. It's not that easy to see but here's the complete 1-1/4 in. pipe bracket arm mounted using floor flanges. The back side is reinforced with plywood. http://www.kbrhorse.net/strpics/ge_79-07.jpg For mast mounts I build the masts out of 2-inch schedule 40 pipe. Not real classy but functional. http://www.kbrhorse.net/strpics/l-m-j02.jpg
Edit: I took a better view of typical wall mounts, in this case with an Intermatic wall mount PC socket. (...)