Rosette Nebula NGC2238
Polar alignment using Sharpcap
Camera Atik One 6.0 CCD
Ha filter
Scope TS optics 65Q
Mount HEQ5 Rowen belts
Guiding PHD2
Control EQMod
Stacked in APP
Levels in DXO
Exposure 46 x 600s taken over two nights
With a CCD there is no gain or black/off set to worry about
Cooling -10deg
Tiff file is 38mb flickr file 7.8mb. Low res below.
https://flic.kr/p/2eVzd1y
I will add RGB next clear night.
What long exposures do.
Forum rules
Please upload large images to photo sharing sites (flickr, etc) rather than trying to upload them as forum attachments.
Please share the equipment used and if possible camera settings to help others.
Please upload large images to photo sharing sites (flickr, etc) rather than trying to upload them as forum attachments.
Please share the equipment used and if possible camera settings to help others.
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MrAstroBen
- Posts: 52
- Joined: Fri Mar 16, 2018 12:19 pm
What long exposures do.
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Re: What long exposures do.
Great image Rob. A good reward for the attention to detail that must have been required to capture & process 7 hours of data.
Dave
Dave
Re: What long exposures do.
Nice image I assume that was through an L filter do you have very dark skies as even on minimum gain of zero I struggle with more than 60s on the ASI1600MM Pro when shooting through the L filter not quite so bad with the R/G/B. All you need now is some more clear nights to get more data good luck and clear skies.
Cheers
Nick
Cheers
Nick
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MrAstroBen
- Posts: 52
- Joined: Fri Mar 16, 2018 12:19 pm
Re: What long exposures do.
Nick,
Shot through a 7nm Ha filter.
My sky pollution is 6/7 . I can run about 240s through an L filter.
There is little luminance data in the Rosette so i will just capture RGB next. Use the Ha as Luminance.
Open a second copy of the Ha and mix that with the red channel.
Using a CCD removes the difficulties associated with setting gain on a Cmos camera.
Rob
Shot through a 7nm Ha filter.
My sky pollution is 6/7 . I can run about 240s through an L filter.
There is little luminance data in the Rosette so i will just capture RGB next. Use the Ha as Luminance.
Open a second copy of the Ha and mix that with the red channel.
Using a CCD removes the difficulties associated with setting gain on a Cmos camera.
Rob
Re: What long exposures do.
Thanks, I did Ha, Oiii and Sii the other week on the Rosette and have been playing with APP today with M42/M43 so may reprocess my data into a more normal coloured image. Thanks for the info I am under 4.5 skies but there is a lot of housing being built around us so will have to see what happens.
Cheers Nick
Cheers Nick
Re: What long exposures do.
A really awesome image, Rob!
Light pollution should never be an excuse not to experiment with longer exposures. Light pollution is signal just like nebulosity. While it is true that you can't image nebulae fainter than light pollution, you will get greater contrast of the visible parts when exposure is increased. The counter-argument is "you can do the same by stacking more". True but be prepared to stack a LOT more. It is not a linear relationship: 100x 1-second exposures does not equal 1x 100-second exposure.
Brian
Light pollution should never be an excuse not to experiment with longer exposures. Light pollution is signal just like nebulosity. While it is true that you can't image nebulae fainter than light pollution, you will get greater contrast of the visible parts when exposure is increased. The counter-argument is "you can do the same by stacking more". True but be prepared to stack a LOT more. It is not a linear relationship: 100x 1-second exposures does not equal 1x 100-second exposure.
Brian