Clavius region, stacked with drizzle 1.5

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turfpit
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Clavius region, stacked with drizzle 1.5

Post by turfpit »

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.

Clavius-drizzle15.jpg
Clavius-drizzle15.jpg (1003.7 KiB) Viewed 212 times


Dave
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oopfan
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Re: Clavius region, stacked with drizzle 1.5

Post by oopfan »

Amazing, Dave!

That is well beyond my ability.

Brian
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turfpit
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Re: Clavius region, stacked with drizzle 1.5

Post by turfpit »

Thanks Brian. Lucky imaging?

Dave
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turfpit
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Re: Clavius region, stacked with drizzle 1.5

Post by turfpit »

Image Before and After Registax processing:

Registax-before-after.JPG
Registax-before-after.JPG (71.06 KiB) Viewed 195 times


These are the settings used. They are guidelines and will vary depending on equipment and quality of data:

Registax-settings.JPG
Registax-settings.JPG (148.46 KiB) Viewed 195 times


Dave
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Re: Clavius region, stacked with drizzle 1.5

Post by timh »

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 ?!

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Re: Clavius region, stacked with drizzle 1.5

Post by turfpit »

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
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