SharpCap Forums

22nd April 2021 around 22:00, Intermittent thin cloud. See links to higher resolution Astrobin images.
Celestron C8, Celestron AVX mount, Altair 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, Exposure=1ms, gain=800/5000
Software: SharpCap 4, Autostakkert!3 (stack best 15% with drizzle 1.5), GIMP.

https://www.astrobin.com/7j0qvt/?nc=user


https://www.astrobin.com/h12pnl/?nc=user


https://www.astrobin.com/ba39hn/?nc=user


https://www.astrobin.com/aro1nr/?nc=user


Dave

Using Virtual Moon Atlas, I have found craters on the image which are only 2 miles in diameter.


Dave

Some great shots Dave!!
Clavius especially really pops. I presume your seeing was good giving the fact the "only" 35fps?

Menno

Thanks Menno. 35fps is the best I can get from the 183M and that is with the capture area reduced to 1920x1200. I think a lot of the detail comes from luck with how the disk is illuminated at the time of the shot.

Dave

The are excellent photos Dave. Hadley Rille especially looks almost 3 D - but they are all good. You must have had focus to a tee as well as good lucky imaging. I guess that f = 2000 mm helps too.

TimH

Thanks Tim. With the C8 I have a JMI Motorised focuser which is on a lead. With the hands-off focusing I can get close to the laptop to study the image. I always

• Highlight Over Exposed in the FX dropdown

• Over expose slightly

• Set Zoom to at least 125%

• Focus by using a crater which has some features in the bottom

• Set Zoom to Auto

• Reduce exposure until Right Hand Side of a log histogram is around 60% saturation

The image on screen looks too dark but it correct for processing. Live (or die) by the histogram! Good focus may take a few minutes to achieve. A 1.5 hour lunar session can produce around 100Gb of data, so it is worth taking the time to get a good focus. If the atmosphere is unsteady then sometimes small craters can appear and disappear in the Live View.




Dave