Jupiter – LRGB imaging

Recently I was aware that Jupiter was approaching opposition, where it is closest in its orbit to the earth. Hence I wanted to take the opportunity to do some imaging of this in mono with LRGB filters. So instead of the Samyang 135mm F2 lens, I switched over to my 8″ Ritchey-Chretien astrograph.Equipment used:

Astro-tech 8″ Ritchey-Chretien telescope, mounted on iOptron ZEQ25, with Pierro-Astro ADC, 1.25″Televue Powermate 2.5x, Xagyl 1.25″ motorised filter wheel and ZWO ASI178MM-cooled.

I used Firecapture to capture the 1 minute videos for each of the different channels – red, green, blue and luminance. I used a gain of 200 and exposure times for each channel of 40-50ms (40ms for red and green and 50ms for the blue channel). These were then pre-processed with PIPP (if required), and then stacked in AutoStakkert!. Wavelets sharpening was then applied in Registax.

Below are three of my best images of Jupiter from that night.

Jupiter with Ganymede
Jupiter with Ganymede
Jupiter with Ganymede
Jupiter
Jupiter with Ganymede
Jupiter with Ganymede

Firecapture was great as I could run through a series of 1 minute captures with each of the filters in quick succession; Firecapture would rotate through the 4 filters in succession while capturing the videos. It would change the filters at the end of each 1 minute video, before capturing the next one. At the end of each series, it would cycle back to the red filter, and wait for me to start the next series of capture. In total I managed to capture about 15 series of these R, G, B & L videos to stack into coloured images. I then used PIPP to create the animated GIF file below.

Animated gif file for Jupiter from 5-6/3/16 night
Animated gif file for Jupiter from 5-6/3/16 night

According to my friend, the seeing was the best he had come across when observing Jupiter. I am pleased that I managed to capture quiter a few images from that night, but I would chalk this experience down as part of the learning process, as I had not done planetary imaging with a mono camera before.

In retrospect, what I would have changed was to image at higher gain such as 300, so I could use faster shutter speeds and capture more frames for stacking. I did find that I did not get much benefit from the Pierro-Astro ADC, perhaps because my 8″ scope was not showing up the atmospheric dispersion, unlike a much larger telescope would.

Also, I would ideally have liked to use my Orion VX12 Newtonian telescope with its 1/10 wave 12″ mirror and greater resolving power, but my observatory is not quite ready to be used just yet. But the Pierro-Astro ADC should make a big difference in a telescope of this size. Oh well, more to look forward to in the future.

Boon