Yep I was using 1600 iso and there is a lot of digital noise, but the problem I have in the picture is the purple area indicated by the arrow.
It isn't a standard high iso noise, it is an area where there is light getting into it. I was thinking a light bleeding inside from the LCD or the LED because the ixus100 with a long exposure keep the leds blinking and the LCD is on.
Would be nice if CHDK could controls this LEDs and keep it of
This is what I've got:
You can see a purple area in the top right border, in the hires photo is much more visible.