DSI strangeness

Hey folks,

I finally got to looking at some of my DSI-Pro frames from August. I've
got this odd interlacing pattern in my images. I've attached a typical
image here. There's been no contrast enhancing, etc. Just a shot of
Plato. A total of 3 images stacked up, 0.0018 exposure each. Using
Meade Envisage software, no dark or flat correction, 8" LX200 at prime
focus.

Any ideas what would cause this ? I haven't seen it in other DSI images
on the net.

Eric.

--
"I feel like I am being nibbled to death by a cat" -Londo Molari