Thanks Riklaunim. The AL chip is the mono chip though, I was wondering about the AQ - or color chip on the ICX655. Despite my best efforts I have been unable to get the QE data on this chip. Strange that Atik doesn't even have this information. I am a bit worried, this chip in a popular microscope camera has 656nm QE at 12% - but then again, it's a different type of camera. I do own the 450C and have had it for almost 2 months but have not had an opportunity to use it yet. I plan to use it for the first time during the new moon (end of January) if I get time. I wonder if there any way for someone like me to measure this or quantify it in some way with astro images other than comparing it to other cameras on the same target for the same amount of time?
-Patrick Holland