Actually there is some image stacking and averaging happening because there's a lot of overlap between the images, and some trials were done with 4x oversamplin

Actually there is some image stacking and averaging happening because there's a lot of overlap between the images, and some trials were done with 4x oversampling and averaging. Probably the next thing to do is to put a diffuser on the LEDs to improve the uniformity of lighting. I think some of the hot-spotting has to do with the radiation pattern of the LED itself, if you just look at it on a blank sheet you can see a bit of a halo on the pattern.