Purple spots on pictures?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Adam Britt by way of Terry Fritz <teslalist-at-qwest-dot-net>" <beans45601-at-sbcglobal-dot-net>

I just got back from taking my tesla coil to school (everyone loved it, of 
cource.) And my teacher took a bunch of pitcures of the coil in action. On 
all of the pictures, these purple spots appear on the pictures. They are 
digital. When he took the pictures, he left the shutter open for 1 second 
to get more streamers on camera. In one of these pictures, there are 4 
purple dots that appear to be a particle that flew off the top load and 
fell to the floor. does anyone know what these purple (and sometimes red, 
white, and blue) dots are? Is it just the digital camera screwing up?
Thanks
Adam  KD5WIT