This was the single best imaging run of 36 runs on a cold evening.
The shadow transit is from Io, the top right moon is Ganymede. Io itself is on the surface of the planet, not easily visible.
Seeing was poor, transparency was poor, and a more than quarter moon was nearby.
Exposures were about 2ms and this was the best 15% of 15k frames. The workflow was: firecapture, autostakkert!, registax, imagemagick, gimp. Not included here is the further processing using winjupos. That will come along shortly.

Below is an animation of the 36 runs of 180 seconds each, totalling 108 minutes

and after even yet more time processing… this is the result of running 36 imaging runs through winjupos to derotate. It was also put back through gimp for black levels, colour saturation and unsharp process (right image).. the left image is the closest timestamped image before winjupos processing.

These results are inconclusive regarding better signal to noise and a better image.