I had good seeing for a long run on Jupiter back on 17th October. I made 25 RGB runs. This animation is over a period of time from 09:44 to 11:19 UT i.e. ~ 1.5 hours.
This aspect is particularly interesting, with the GRS fairly central at the start and rotating right to the limb by the end. The fact you can see it almost edge on is a testament to the seeing throughout. Io moves in, to then transit the planet as the Oval BA rotates into view..
Processing the 43 images that makes up the animation was difficult and time consuming, especially when the captures are monochrome RGB and not OSC. In fact a colour camera would make things very much easier, but the compromise is on image quality. Here is a summary of the process:
- -processed the 75 videos with Autostakkert 3! and RegiStax6
- -measured each image in WinJUPOS using the wide field calibration image. This takes time for the first image but each subsequent image is already aligned so it is a matter of opening up the image, checking all is good and saving it to disk. As I had made the captures in 3 batches, there were gaps in between. Using WinJUPOS I derotated some of the captures each side of the gaps to fill them in.
- - for each Colour Channel I integrated the measured images in lots of 3 and 4……234, 2345, 345, 3456, 456….etc to produce as many high quality images as possible, with a minimal time between each image. For the above example, the timestamps of each image are 3, 3.5, 4, 4.5, 5 etc. Each capture is 1 minute, but since I do RGB and IR in sequence, at 1 minute each it is 4 mins between successive images of a particular colour channel and therefore also for a particular RGB combination. By integrating in lots of 3 and 4 I get an image for each 2 mins. Had I integrated 234, 345, 456 for example, I would have ended up with images 4 mins apart.
- - I ended up with 43 combined images for each colour channel.
- - 43 RGB derotated combinations of the corresponding R, G & B images in WinJUPOS were then produced
- - sharpened and RGB balanced each image in RegiStax
- - applied denoising and unsharp masking, then Curves Transformation to improve image contrast in PixInsight. I used a process container here which was hugely beneficial, in that I did the work on the first image and then applied the process container to each subsequent image to have it complete the steps quickly and efficiently.
- - separate red, green and blue images of Io were aligned & integrated in Photoshop, before RGB combination. The resultant colour Io image was subsequently added to the various Jupiter images.
- - combining and derotating images from multiple runs, means multiple ghost images of the moon Io. This is a particular problem when the moon is over the planet. Therefore I had to make single RGB combinations at the appropriate timestamp and process these to give me an image without the ghost images. I put the single RGB image in layer under the integrated image, and used a mask to paint over the ghost images and reveal the planet in the image beneath. This process is difficult and not always perfectly successful, as you may be able to see.
- - I made a template for each image from the WinJUPOS Ephemerides showing the position of the Moon with respect to the planet. I used these to insert the image of Io at the correct location for each image and its timestamp.
- - the final animation was done with EasyGIF Animator. This does as good a job as any of producing GIF animations, but unfortunately it doesn’t preserve the original image quality and does clip some of the brighter regions.
Here is a DropBox link to an MP4 video file which is of higher quality:
https://www.dropbox.com/s/26jv2yxoep5myyb/Jupiter%20Animation%202021-10-17.mp4?dl=0It really wasn’t worth the time spent doing this but then again it is raining. :-)…..perhaps a once a year exercise and something I did during the days and days of cloudy weather and rain we've been experiencing..
Version B is an integration of 9 runs to produce a single image.
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