Quote:
Originally Posted by Bart
Finally got some colour for my NGC104 image. Not very much or not as much as I wanted although for now it will have to do. Still struggling with focus, will try to get out under the moon and nail the Temp Compensation and see how that goes.
Details
Telescope: William Optics FLT132
Guide Scope: QHY OAG
Camera: QHY9 Mono @ -20c
Filter Wheel: QHY 7 position Ultra Slim
Filters: QHY 36mm unmounted L R G B HA OIII SII
Guide Camera: QHY5L-II
Mount: AZ-EQ6
Mount Control: EQASCOM
Focusing: SharpSky Pro and Sequence Generator Pro 3 (automated)
Bahtinov Mask: No
Capture Software: Sequence Generator Pro 3
Guiding Software: PHD2
Calibration and Stacking Software: PixInsight
Processing Software: PixInsight
Number and Type of Data Frames: L= 19X300 sec, L =7X120 sec, L= 14x30 sec, R= 10x180 sec, G= 10x180 sec, B= 10x180 sec
Ha= x , SII= x , OIII= x .
Binning: 1x1
Total Image Time: 206 minutes
Location: Lockleys Observatory B, Tanunda, Sth Australia
Light Box by Exfso
Full Res
http://www.pbase.com/image/168197638 |
That turned out very well.
With temp compensation I found keeping a log of the temperature and the focus positions and then working out an average number for the shift of focus/ degree C worked pretty well. It does assume focus shifts are linear and they probably are initially then they flatten off (I think or at least they seem to with my scope). Most likely due to a closing of the difference between ambient and the temp of the objective.
For example my CDK17, when the temp difference is more than 1C it will not be spot on focus but once its within .5C it reaches a peak and focus is sharp.
Greg.