Sorry guys not as much time to spare lately in imaging. Lousy weather with high moisture and some fog didnt help yesterday either.
Struggled to get as much data as i could, just poor conditions.
Of course the bad light pollution in this area doesnt help.
I really need to get a IDAS LPS filter, as its just a shame to waste such a great scope on sky glow.
Too boot, i noticed some PEC in the subs, so i have to fix it in PHD next time.
Quickly processed, with a little too much sharpness.
Sorry for the tiny file size guys.
Scope CDK-20
Camera QHY-8
Exposure 140 minutes (30x5 minute subs)
Cropped slightly to remove drift (Alignment, another thing to fix one day !).
OOPS, sorry, forgot : No darks flats or bias used either.
Nice Theo! Good to see an image out of this scope after having waited so long! Some of the stars look a little fatter than they should given the detail in the nebula etc, is that a bi-product of the processing or something else?
up close and personal ... whats the FL of this scope?
Hi Clive,
Focal length's 3454mm, so a bit of a challenge for the guider.
Quote:
Originally Posted by AlexN
Some of the stars look a little fatter than they should given the detail in the nebula etc, is that a bi-product of the processing or something else? ...
Hi Alex,
At these focal lengths, with atmospherics and sky glow, they will be larger than normal.
The FWHM on focussing i got nothing under 5 during the session.
Even my secondary started fogging up with dew.
Heres one when conditions werent as bad, its the Bug nebular. Exposure is a single 2 minute frame.
Looks like the seeing may certainly have hindered here but could also be the processing, that scope is by all reports a corker. Mike Berthon-Jones has a 12.5" CDK and his images from reasonably light poluted western suburbs of Sydney are mighty fine with very tight stars. While I suspected it due to amazing images from Philip Kellers scopes, Mikes images are enough to suggest that the CDK is a better scope than an RC.
Keep at it, I look froward to seeing what comes from this moster scope.
Mike Berthon-Jones has a 12.5" CDK and his images from reasonably light poluted western suburbs of Sydney are mighty fine with very tight stars. ... ..
Theres a big difference in focal length of 1000mm between the 2 scopes, and that makes a huge difference when conditions are poor. You just magnify more seeing error with the longer FL.
As shown with the sigle sub of the bug nebula, a huge difference during different nights of seeing.
During that night i got just over 3 FWHM on focusing.
Star dancing was near non excistent.
Speaking about the 12.5" CDK, it is a popular scope, but i think with these new cheaper RC's, its going to be a real big competition.
Don't know if it was seeing or poor focus, though it can be difficult to obtain focus when the seeing is poor at this FL. I'd be placing more attention to your skills at the computer as I don't feel you're getting the maximum from such an instrument. Apologies if this sounds blunt, but when you've paid the mega bucks, I'd be expecting the mega images. The data appears to show promise. Very keen to see how you progress - keep at it.