I was shooting in a cave in Sri Lanka I took 3 pictures on a tripod, and this is the last of the 3.
In the upper right hand corner is a shadow with some kind of purple streak. This is the first time something like this happens on my Pentax K-x, and never happened again. Is this a sensor problem or static electricity discharges of some kind ?
This is a crop of the image.
I posted it at the pentaxforum.com. A member there think that it is a violet shirt. On closer inspection the shadow do looks very similar to a t-shirt. Guess I was too busy looking through the viewfinder.