Jupiter, 2020 Opposition
August 2, 2020.
July 16, 2020. Average seeing but clear skies were predicted for the wee hours of this morning. I opened up the observatory around 1:15 AM and lined up on Jupiter with the ASI183MC (2.4 micron pixels) at the f/14 focus of the Schupmann. I was able to obtain 6 one minute videos before a cloud spoiled my fun. An interesting circular white storm appears on the northern edge of the NEB right on the meridian. See derotated stack of all six images (each an aligned and sharpened stack of the best 5% of almost 10,000 frames of each video) and an animated GIF below.
July 14, 2020. The CSC predicted average seeing for most of the night after July 14. Set alarm to 11:30 PM. Sky was clear and Jupiter bright. Opened up and set the ASI183MC at the f/14 unamplified focus of the 7.25" Schupmann. Seeing was definitely below average, contrary to the CSC prediction. Focus difficult. Used Bahtinov mask on one of the satellites to focus and then tuned out atmospheric dispersion with the field mirror adjustment screws on the Schuppy. 5.125 ms sufficed to achieve a 60% saturated histogram at a gain of 354. The ROI was adjusted to 544x446 and film speed of 150 fps resulted. A set of ten 1 minute videos was taken, the last two being unusable because of rapid deterioration of seeing to awful. Videos processed in AS!2 keeping the best 10% of the frames and the resulting TIF files sharpened in Registax. The first 8 of the resulting images were derotated and stacked in WinJUPOS and again lightly sharpened to give the result shown below. All 10 of the images (including the last two very fuzzy ones) were used to prepare the animated GIF shown below. The satelite is Io.
June 20,2020. Seeing was quite good but transparency low when I took 27 one minute videos of Jupiter with the ASI224MC camera coupled to the 7.25" Schupmann with a 2x Barlow lens. The four images below were prepared from the sharpened stack of eight imges prepared from the best 20% of the 3212 frames of one minute videos. The animated GIF was prepared from all 27 of the images.
June 15, 2020. Seeing was predicted to be good this morning, so I got up at 2:30 AM and set up the Schupmann with a 2x Barlow and the ASI224MC one-shot color video camera. After getting a good focus and tuning out the atmospheric dispersion I obtained a series of 50 one minute videos of Jupiter. Seeing was good at the beginning of the session, but deteriorated gradually. Europa was in transit near the Eastern limb and the Great Red Spot just appearing at the Western limb at the begining of the session. The annotated image below was made by derotating and stacking the images obtained from the first 8 videos. Each of the images was a stack of the best 8% of the 6193 frames taken with a 9.6 millisecond shutter and a gain of 60%. The animation was made from the images from all 50 of the videos. Note how the seeing deteriorated.
June 11, 2020. I took the 21 best images from the 47 videos I took on the morning of June 10 and derotated and stacked them to get the attached result. I used the sharpness of the dorsal fin of the little shark shaped festoon on the north edge of the EZ as my criterion. Came out a little better than the stack of all 47 images. Of course, nothing beats getting better seeing. A storm front just passed through here. No winds, but buckets of rain. Slacking off now. The forecast for the next several days is pretty grim for imaging. Looks like next Wednesday morning is my next chance.
June 10, 2020.
Seeing was considerably better this morning than it was yesterday, although a bit variable, as was the transparency. I took 47 one minute videos with the
ASI224MC, 2x Barlow and 7.25”, f/14 Schupmann medial. The combination gives an efr of f/26.7. I used a 19.6 ms shutter and a gain of 343. Each video contained 3049 frames.
Autostakkert!3 was used to align and stack the best 15% of the frames from each video and the resulting images were sharpened with wavelets in Registax6. WinJUPOS was then used to
derotate and stack the images in groups of 7 adjacent-in-time images and also to produce a derotated stack from all of the images. All 47 of the images were then combined using GIMP to produce an