Is anyone here imaging with a TEC140 or TEC180 (or other APO) using a Trius (or other brand camera with the ICX694 sensor?
I'm getting very bloated stars in the blue channel, and bloated stars in Luminance. I'm using focusMax & Baader filters. No matter how well I focus I end up with what looks to be an out of focus blue channel. I've even gone so far as to try creating separate v curves just for the blue filter. The odd thing is that CCDInspector will report rather decent FWHM values for blue.
I realize that atmospheric distortion will have a greater impact on blue but I think what I'm seeing is abnormal.
If you are using the ICX694 successfully or unsuccessfully with a TEC or other APO I would really appreciate a reply. My gut feeling tells me that this might be due to the increased sensitivity of this sensor perhaps dovetailing with something about the way the TEC scopes may be corrected. I'm particularly curious to know if this kind of issue is seen with different brand APOs, or different brand cameras.
The blue channel was taken earlier in the evening just west of the meridian. I took some shorter exposures that have a bit better FWHM which would indicate tracking and or atmospheric contributions. However even those shorter images show the bloat and out of focus look.
Image shown at 160% in order Blue, Green, Red
PS Another imager in Australia is having a similar issue with bloated stars on his TEC180/Trius combination. Though it isn't yet confirmed that he sees this in the blue channel only. It is quite obvious in Luminance, however.
Edited by PRejto, 21 September 2014 - 02:08 AM.