Tom, if you want to send it in, please contact @Bill for service. Bill (at) SBIG (dot) com. Please send FITS files, raw, unprocessed, binned 1x1, no dark or bias subractions, shot through a clear slot (no filters). We'd want bias, dark, light frame. The dark should be the same length as the light. Have you double-checked that your filters are in the correct orientation (shiny side toward the telescope) ?