The Moon and Jupiter (and more moons…).
I didn’t get around to a writing post this week. It just didn’t work out this week, with other priorities and things to do. However, on the 17th, there was a nice clear night, so I did manage to get the scope out. The moon is approaching fullness, so deep sky photography is out, but I thought I would have another go at Jupiter and maybe try my hand at a Moon Mosaic for the first time. I’ve seen other people’s and I’m really impressed with the detail, so thought I’d give it a go.
First off, I pointed the scope at the Moon, it was in a better position and higher in the sky than Jupiter, so I left the planet to rise a bit higher to, hopefully, minimise the effects of the atmosphere on the view.
The ZWOASI120MM camera I currently use has a much smaller sensor than my DSLR, so gives a much narrower field of view. It can’t get the whole of the moon in one go anyway, so a mosaic was definitely the way to go. I found the top left of the moon in the scope view and took 3x60s AVI movies on the left and then 3 on the right, going back up the other side of the moon.
By the time this was finished, I turned to Jupiter which was a bit higher and a took a 60s AVI using the ZWO camera, but with the addition of a 2.25x Barlow to increase the size of Jupiter slightly. As luck would have it, I managed to time it right to coincide with the transition of Calisto (one of Jupiter’s moon) across the surface of the planet, so I caught the moon’s shadow as well.
I also took another 60s AVI of Jupiter, but over-exposed it so that Jupiter was a bright blob, but 4 visible moons showed up in the image – more about that later!
Then I packed up and withdrew to the warmth of the house and a chance to play with the images.
I started with Jupiter as that was probably easier.
Each video was processed in PIPP to get rid of the dodgy frames (I kept 10% of them) then into AUTOSTAKKERT to stack the frames. Finally, I put the images into REGISTAX to play around with the wavelet function to try to pull out some detail.
I then had two images – one of Jupiter and the shadow of Calisto, and one of the moons. After a bit of trial and error in Photoshop, I managed to get the two layers to work together and merged them. I used the magic eraser function to bring Jupiter up into the image with the moons, replacing the over-exposed Jupiter with the more detailed planet.
I was pretty happy with the result, which included Jupiter, the four moons and the clear shadow of Calisto on the bottom of Jupiter (or it might be the top… it’s space, who knows….).
It still bakes my noodle that something (r) 700,000,000 km away can be seem through such a small piece of kit.
Then it was on to processing the Moon. Each AVI was run through the same process as the Jupiter AVI but, after sharpening in Registax, I cropped the images with clean edges before putting them together in Microsoft ICE, a free bit of software that stitches panoramas together and works pretty well with Lunar Mosaics as well. It is pretty easy to use, but you do need to make sure your images overlap, so it can line them up. However, you also need clean edges, otherwise it all goes a bit awry. Other people recommended iMerge and HUGIN, but I didn’t get on with them so well, and MICE worked, so will use that until it finds something it can’t cope with.
Finally, when all stitched together, I popped it into Photoshop for a quick tweak and ended with a nice, detailed Mosaic, that I am very happy with as a first effort.
Of course, now I’m thinking about scopes with longer focal lengths to get closer to the target…
The full size images are in the Gallery, if you want to take a look and let me know if you have any questions!
Posted on March 20, 2016, in Astronomy, Astrophotography, Uncategorized and tagged AUTOSTAKKERT, avi, calisto, hugin, imerge, jupiter, mice, moon, photoshop, PIPP, REGISTAX, transit. Bookmark the permalink. Leave a comment.