I went into the studio to put my sneakers on because I left them there last night. No need to turn on the lights because I could see them in the dimly lit room. As I finished tying the laces I noticed that I had left the stand light on in the iso booth. Needed to shut that off before I went back to the kitchen. Baaammmmm! Aha! Didn't notice that the second sliding door to the Iso booth was shut.