Jupiter and Io's shadow

Finally got a clear shot at Jupiter

along with a bonus Io shadow transit:

animation of the tail end of the Io transit:

Io transiting Jupiter

Imaging details

had hoped to image jupiter over christmas break, but nothing but rain and clouds.  pristine skies afterwards, but with seeing so poor stars were flashing like fire engine lights.  managed to get one night of not terrible seeing for this capture.  

a few technical difficulties led to gaps in the capture.  

captured a total of 16 sequences.  processed them all in win jupos then photoshop only to realize that it was too long a time span actually degrading the quality of the image.  

then re-did the whole thing with only 9 images.  

tried bigg sky again. the problem was that the seeing wasn't great so had to smaller stacks (excluding 50%) in this situation bigg sky tends to add noise, so i processed luminance only which muted the colors.  the final image above is mostly registax.  

here are full scale animations with the two techniques.  

note that bigg sky requires sharpening before derotation.  so you wind up with sharpening artifacts that are mitigated by stacking after derotation.  

conversely using wavelets, i undersharpen the individual captures avoiding noise, then push the sharpening after derotation/stacking when there is less noise.  

Bigg Sky

registax

raw stretched stack after derotation

Bigg Sky

registax