I think I finally done all of the things suggested here so far. Shown is the shot last night. In addition to the previous update, I have done the following:
(1) Used FireCapture. The 2.7 beta version runs on Mac! It is a game changer. With the auto-center feature, I can spend a long time to dial in focus. I can now more consistently achieve better focus. Would a autofocuser make the focus better? . The ROI and cut out feature helps with the frame rate. In this shot my frame rate was 140 fps. Also the sequencing is very helpful, reducing a lot of time staring at the screen like an idiot sitting in the yard while the neighbors sleeping .
(2) Reduced the back focus and screwed the Barlow element on to ASI462MC nose piece. The effective f-ratio is 17 according to the log. This also helps with the frame rate. Much brighter image.
Last night Jupiter was wobbling quite a bit. According to medeoblue the jet stream was above 30 km/s and the second seeing index was 1/5. Nonetheless, the image turned out be decent with 10% stacking in AS3.
Part of fun of astrophotography is experimenting for better results. I think I can say that this forum really gave me very sound advice
Edited by HarveyDeckAstro, 30 September 2021 - 10:55 AM.