View Full Version here: : Another frustrating night!
peter_4059
20-02-2011, 01:32 PM
Conditions were looking promising last night so I decided to give the Ha another try. I went through all the prep including colimating, checking the scope visually for astigmatism, drying out the camera for a week with silica gel etc. Things started off bad when I discovered a small hair on the inside of the IR filter. :mad2: Pulled the camera apart, cleaned all surfaces and back into the bag with silica gel. I took the opportunity to drift align the mount and this turned out to be time well spent as the guiding improved dramatically thereafter. After reassembling the camera I managed to get 100 mins on the Horsehead before it disappeared behind the trees. I then turned to the Gabriela Mistrel (NGC3324) and got 100 mins before packing up at 3am.
As expected the horse could have done with more subs to bring out the detail while keeping the noise at bay. I was surprised at the NGC3324 image once I'd processed it - seems to have picked up some strange bands - not sure if this is from the full moon rising or possible dew on the primary?
Anyway not a great deal to show for 8 hours however at least I confirmed the primary is not pinched and the polar alignment is now a lot better.
Thanks for looking.
desler
20-02-2011, 02:17 PM
Looks like you've picked up something in the mistral neb, frosting or mosture somewhere.
You are getting plenty of detail though, how long are the subs?
Darren
peter_4059
20-02-2011, 02:21 PM
Darren,
I did 10 min subs on the HH and 5 min on the Mistral neb. It was pretty steamy up here last night so you are probably right about the frosting.
multiweb
20-02-2011, 02:54 PM
That HH looks hot! :thumbsup: Funny stripes on the Eta shot. Looks cool though.
[1ponders]
20-02-2011, 03:00 PM
Nice Pete, but you still have those funny shaped stars. What's happening there?
telecasterguru
20-02-2011, 03:12 PM
Not too shabby considering.
ozstronomer
20-02-2011, 03:17 PM
The Horse Head looks great, shame about the banding on the mistral neb.
Is it a reflection radiating from a central point under the image???. Hope you can sort out the dew problems as the Mistral has plenty of detail in it
peter_4059
20-02-2011, 08:37 PM
Thanks for the feedback.
Still not sure whats up with the stars in the HH shot Paul. I think I've ruled out colimation and astigmatism. Guiding was pretty good. Seeing? Tube currents? It was a pretty hot night. The mistral neb stars looked a lot better however the subs were half the length.
allan gould
21-02-2011, 05:52 PM
Both look good Peter. The Mistral Nebula could have been affected by the moon as it was high up at the time your photos were accumulated - but its still a nice shot.
Allan
adman
21-02-2011, 05:59 PM
I've seen that type of banding before....usually something reflective in the ota....yep definitely 80gsm A4 Reflex paper. ;)
peter_4059
22-02-2011, 07:50 PM
Thanks Allan - I was wondering if the moon was the culprit?
Adam - yep, gotta watch that 80gsm!
troypiggo
23-02-2011, 11:18 AM
*cough* *cough* somebody talking about paper on the primary here?! :(
peter_4059
25-02-2011, 07:34 PM
While setting up tonight I think I've got an answer for the source of the bands in the second image - the heads of the bolts holding my moonlite focuser in place on the inside of the OTA are nice shiny silver stainless steel and they are sitting right under the secondary. I reckon it was light from the full moon reflecting off one of the bolts onto the secondary. They are now flocked!
[1ponders]
25-02-2011, 07:41 PM
for a moment there I though you were profanity filter bypassing lololol
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