graham.hobart
17-05-2014, 05:13 PM
Hi folks. This is NGC 5247 taken recently- my first light with the new RC 10.
It was shot with a full frame Canon 5 D mark II and the original GSO focuser that came with the scope. It was guided with an off axis modded guide scope with a barlowed Lodestar.
I request critique on several points and to that extent have posted the uncropped frame.
As you can see there is no flat frame correction - my flat box is hopefully being constructed now (thanks Pete).
This has only been calibrated with darks and bias frames stacked median sigma with DSS and slightly processed in Star Tools and PS 5.
It was approx 4 hours 15 minutes of lights-mostly 1600 ISO but some 800- I started shooting ISO 1600 because I thought the clouds would come back but actually got three and a half hours one night clear!
My queries are
1/ considering the article Paul (Haese) wrote about reflections in his RC 8- is that what I am suffering from in the top middle of the shot? Maybe from Spica off camera?
If so should flocking the baffle sort it as in Pauls fix (sorry Paul to namecheck you but you seem to be the guy with most experience a la GSO RC's)
2/ there seems to be a general fogginess in the picture which is maybe not all the gradient. Taking away the fact that there was a Moon and I have light pollution, and it was a DSLR whose EXIF was getting up to 30'c after a while - is is there still likely to be any improvements I will be getting when my feather touch focuser gets here- i.e is there an element of poor focus that would be improved with more rigorous technique (too small Bahnitov mask, crud focuser, etc)So if you imagine that frame flat corrected with say, focus max running a CCD - do yo think some of that fuzz would go or should I move house or try narrow band?!!
I mean some of the stars seem to be in focus - which brings me to the next point. I have borrowed a Tak scope to collimate but haven't tried yet as I saw no point till my focuser turns up, but looking at the stars in the corners is there a way to predict or have an idea about the direction of collimation by looking at the stars in each corner? I have included the four corners in magnification and the ones in the bottom left are not that bad really.
Sorry for the long winded note but I thought I would celebrate passing my 1000th post recently in style! (only took me four years!!)
Please feel free to flog this pommie Tasmanian and let me know your learned opinions. Being the token pommie at work and working in Tas you do develop a thick hide!!:lol:
Thanks mates
Graham
Pictures are firstly uncropped frame, then crop of top left then top right then bottom left then bottom right :thumbsup::cloudy::cloudy:
It was shot with a full frame Canon 5 D mark II and the original GSO focuser that came with the scope. It was guided with an off axis modded guide scope with a barlowed Lodestar.
I request critique on several points and to that extent have posted the uncropped frame.
As you can see there is no flat frame correction - my flat box is hopefully being constructed now (thanks Pete).
This has only been calibrated with darks and bias frames stacked median sigma with DSS and slightly processed in Star Tools and PS 5.
It was approx 4 hours 15 minutes of lights-mostly 1600 ISO but some 800- I started shooting ISO 1600 because I thought the clouds would come back but actually got three and a half hours one night clear!
My queries are
1/ considering the article Paul (Haese) wrote about reflections in his RC 8- is that what I am suffering from in the top middle of the shot? Maybe from Spica off camera?
If so should flocking the baffle sort it as in Pauls fix (sorry Paul to namecheck you but you seem to be the guy with most experience a la GSO RC's)
2/ there seems to be a general fogginess in the picture which is maybe not all the gradient. Taking away the fact that there was a Moon and I have light pollution, and it was a DSLR whose EXIF was getting up to 30'c after a while - is is there still likely to be any improvements I will be getting when my feather touch focuser gets here- i.e is there an element of poor focus that would be improved with more rigorous technique (too small Bahnitov mask, crud focuser, etc)So if you imagine that frame flat corrected with say, focus max running a CCD - do yo think some of that fuzz would go or should I move house or try narrow band?!!
I mean some of the stars seem to be in focus - which brings me to the next point. I have borrowed a Tak scope to collimate but haven't tried yet as I saw no point till my focuser turns up, but looking at the stars in the corners is there a way to predict or have an idea about the direction of collimation by looking at the stars in each corner? I have included the four corners in magnification and the ones in the bottom left are not that bad really.
Sorry for the long winded note but I thought I would celebrate passing my 1000th post recently in style! (only took me four years!!)
Please feel free to flog this pommie Tasmanian and let me know your learned opinions. Being the token pommie at work and working in Tas you do develop a thick hide!!:lol:
Thanks mates
Graham
Pictures are firstly uncropped frame, then crop of top left then top right then bottom left then bottom right :thumbsup::cloudy::cloudy: