22nd April around 21:15. Intermittent thin cloud.
Celestron AVX mount, Celestron C8 SCT, Altair Astro 183M (camera has an IR cut filter sensor window). Hands-off focusing with JMI Moto-Focus.
Capture area = 1920x1200, 8-bit MONO, SER, 60s @ 35fps = 2000 frames, exposure=1ms, gain=800/5000.
SharpCap 4, Autostakkert!3 (stack best 10% with drizzle 1.5), Registax 6 (gamma, contrast, brightness, layers 1 2 3) GIMP (crop).
The last one! 19/21/22 April, the 3 nights (around 5 hours) resulted in ~250Gb of data.
Dave
Clavius region, stacked with drizzle 1.5
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.
Re: Clavius region, stacked with drizzle 1.5
Amazing, Dave!
That is well beyond my ability.
Brian
That is well beyond my ability.
Brian
Re: Clavius region, stacked with drizzle 1.5
Thanks Brian. Lucky imaging?
Dave
Dave
Re: Clavius region, stacked with drizzle 1.5
Image Before and After Registax processing:
These are the settings used. They are guidelines and will vary depending on equipment and quality of data:
Dave
These are the settings used. They are guidelines and will vary depending on equipment and quality of data:
Dave
Re: Clavius region, stacked with drizzle 1.5
That is fantastic Dave
How close are you to the theoretical resolution limit? 0.56 arcsec for an 8 inch telescope -- drizzling to make sure that it is sampled finely enough. If Clavius is 140 mile across then it looks as though you are resolving features maybe only 1% of the diameter? My rusty trigonometry says that you must be resolving down to an arcsec or so ?!
TimH
How close are you to the theoretical resolution limit? 0.56 arcsec for an 8 inch telescope -- drizzling to make sure that it is sampled finely enough. If Clavius is 140 mile across then it looks as though you are resolving features maybe only 1% of the diameter? My rusty trigonometry says that you must be resolving down to an arcsec or so ?!
TimH
Re: Clavius region, stacked with drizzle 1.5
Thanks Tim.
I have never thought about it in that detail. There is a crater at the North of Clavius called Porter, within Porter there are 3 small craters. By comparing with the Clavius Top Picks on Astrobin, I can match the 3 small craters in Porter. The better images tend to be larger SCT's. I am happy with what I am producing. I tried stacking with drizzle 3.0 but the result was poorer.
It is humbling to think that the distance from Liverpool to Hull is 128 miles, which would fit inside Clavius.
The biggest asset I have for the C8 is the JMI hands-off motorised focuser.
You have got me wondering what is the smallest crater in that image?
Dave
I have never thought about it in that detail. There is a crater at the North of Clavius called Porter, within Porter there are 3 small craters. By comparing with the Clavius Top Picks on Astrobin, I can match the 3 small craters in Porter. The better images tend to be larger SCT's. I am happy with what I am producing. I tried stacking with drizzle 3.0 but the result was poorer.
It is humbling to think that the distance from Liverpool to Hull is 128 miles, which would fit inside Clavius.
The biggest asset I have for the C8 is the JMI hands-off motorised focuser.
You have got me wondering what is the smallest crater in that image?
Dave