My son recently acquired a Celestron NexStar 4SE in June, and on July 12th, the night was looking a bit clear. He was heading to bed but gave me permission to play with his scope. Alignment worked perfectly, I tried for a few things to see, etc. And that was my intent — solely to test the alignment and take a peek at the moon and planets.
Except I was curious how it would fare with my iPhone for simple astrophotography. I captured the images and video, but then I let them sit in my folders for a bit. So much so that when I finally did start playing with them, I totally forgot they were taken on the 4SE, not my standard 8SE. I was a bit disappointed with my processing, but when I realized earlier today they were all on the 4SE, my expectations changed!
So the equipment was a Celestron NexStar 4SE, with stock alt-az mount and tripod not set in wedge mode, iPhone XS Max, 25mm plossl, and the Celestron NexYZ phone adapter. By the time I started imaging, the moon had set behind the neighbour’s house, so I was focused on planets.
First up is the first single image. Camera settings were f/1.8 (hardset in the phone), ISO24 so it isn’t overblown, and duration of 1/9s. I took a series of them with a remote shutter release to prevent shaking. The result is a little faint, but something there that is clearly Saturn.
Cropping it makes the image a little clearer:
The best one of the set of 55 images is this one:
Cropped and flipped, it looks like this:
I tried stacking the photos using Affinity, with noise reduction, keeping 75% of the images, and this is what I got:
I took a video file too that night:
If I take that video, and run it through the astro programs PIPP and Autostakkert, with stacking, cropping, brightening, etc., I end up with this:
A different set of settings, without the brightening, game me this:
If I push that through Registax and play with basic wavelets and brightening, I get this:
The video file has 1200 images/frames, so it should be showing me way more data, but I’m not that great at processing yet.
I wanted to go back and try a stack in Nebulosity 4 (which an online friend uses with great success for DSOs), even though it is not able to handle videos plus it isn’t necessarily the best option for processing planets. Nevertheless, I force-fed it the 55 images, normalized them, culled for quality, and then stacked the final 45 images. This is the result:
Which an online friend took, downloaded, and re-colorized to be a bit more “normal” for Saturn, to give me this:
And another friend did this off the original video:
The stacking options of PIPP/Autostakkert with 1200 frames gave me almost the same outcome as Nebulosity with 45 images. Overall, I’ll settle for either one for an early effort, whether it was with a 4SE or the 8SE. Auspicious progress.