Jupiter!

The current full moon (the Full Beaver Moon) limits deep sky imaging, so I dug out my old first-generation ETX 125 OTA (I still have the original drive base and Autostar and they still work) and mounted it on the iOptron SmartEQ Pro GEM and set out to image Jupiter last night. My camera of choice for this session is the Mallincam Skyraider-SLP. Although it is a USB 2.0 camera, it can capture at a pretty decent speed at 1024 x 768 resolution.

The first image is a stack of approximately 2,400 images (best 70% of a stack of 3,000+) captured at 45 fps at 1024x768 with a 2x Barlow (f/30). The images were stacked and processed in Registax 6 and tweaked in AstroSurface, Affinity Photo, and Microsoft Photo. I happened to start imaging just as Io started a transit across the disk (I only saw it after processing); Io is visible to the left just entering the disk. The Great Red Spot and several whorls and condensations in the cloud belts are also visible in the image. Given the 5-inch aperture and the fact that the wind was shaking the mount throughout the imaging session, the result is not too bad.

Despite the wind, imaging conditions and seeing were quite decent. I decided to pull out a piece of equipment I have never used—a 5x Barlow. Of course, imaging at f/75 has some challenges (!). The biggest issue was that the capture rate fell to 4.5 fps. I could have boosted gain, but I find that gain adds a great deal of noise to captured video images, and I never boost it above 40%. I was surprised to see a usable image, and I captured about 2,500 and stacked about 1700 for the second image. The biggest disadvantage is that the slow capture rate cannot counteract atmospheric blurring. The result is a smooth and “artistic” looking image, but without much detail (Io was still transiting, and it cannot be seen in this image). UPDATE: Thanks to the advice of a colleague on the Mallincam Group, I RGB balanced these images. I used Dyadic wavelets in reprocessing, and Io can now be seen in the second image, too, transiting toward the middle of the same belt as the GRS (the South Equatorial Belt [SEB]).

All in all, I was pretty happy with the session. I’m looking forward to Mars a little later in the month when it will be well placed for imaging from this site.