# Lucky imaging with Celestron 14 - is this result reasonable?

I attempted to do some lucky imaging of Jupiter using a permanent installation (Celestron $$14$$" SCT + Paramount ME II) and Nikon D5600 attached directly to a Baader Hyperion 8-24mm eyepiece (without a filter). The atmospheric conditions weren't ideal ($$65$$% humidity, $$2$$ m/s winds), the telescope was properly acclimated prior to use, and Jupiter was around $$17^{\circ}$$ elevation during imaging.

After processing $$3600$$ frames (from 1 minute of video1 at $$60$$ fps) with Autostakkert 3 and then aligning the RGB channels and recomposing I got these:

Left (or top if your screen is small) is using $$20$$% of the stack, right (or bottom) is using $$50$$%. Since this is my first foray into planetary imaging my question is: are my results reasonable given the setup used and atmospheric conditions described?2

I'm asking because I've seen much better results from people using smaller telescopes. I think the discrepancy is the result of one (or several) of the following:

1. Something is wrong with the equipment I used.
2. I'm using the wrong equipment.
3. I'm not processing the images correctly.
4. This is the best the equipment could do under those conditions.
5. I did something wrong in my setup or imaging.

and I'm trying to rule out number 1.

Here is a single, unprocessed frame for reference:

## Update

I have acquired a Bahtinov mask to rule out the focus as the issue, here is an exposure of Manubrij (Omnicron Sagittarii) with the mask:

At the time of imaging, the angular separation between Jupiter and this star was less than $$6^{\circ}$$. Conditions were much better this time, humidity was $$38$$%, winds were less than $$1$$ m/s. The telescope was acclimated for about 2 hours prior to use.

Again using $$3600$$ frames af $$60$$ fps I got these:

Left (or top) is with $$10$$% of the stack, right (or bottom) is with $$20$$%. This looks slightly better to me, but I'm still not sure if this is what I should expect from the equipment.

1 Note that the video in the link has been compressed through ffmpeg using the H.265 codec with CRF of $$25$$.

2 This result is just one example - I did $$30$$ minutes of imaging in $$3$$ minute segments over the course of several hours, applying the same process to other sets of exposures yielded similar results.

• Beautiful photos! Astronomical seeing is constantly changing, you can think of it as there being a lot more luck available on some nights than others and in some places than others. It also varies from one location to another, may be better at higher altitude, and in different seasons. Check to see if the images you compare to are from winter rather than summer and/or from the tops of mountains, or past midnight...
– uhoh
Jul 10, 2020 at 10:27
• @uhoh I've been hoping it was just the seeing since conditions in my location are typically poor -- although it was better than usual when I took these. I just don't have any reference since this was literally the first time I tried lucky imaging. Jul 10, 2020 at 10:31
• I do believe that with better seeing and preferentially higher altitude you might get considerably better images. you might also want to try longer video sequences and use a smaller percentage - especially as Jupiter won't rise to higher elevation anytime soon. Try playing around with some image sharpening options on what you show here. Jul 10, 2020 at 10:37
• @planetmaker I have 30 minutes of video over the course of several hours, so I will definitely follow your suggestion. I'm also trying to use DStation to deconvolve what I have here as much as possible... the noise on the composite produced by 20% of the stack hinders the deconvolution - another reason to use a longer sequence. Thanks for the input Jul 10, 2020 at 10:42
• I agree with @planetmaker that elevation is likely an issue. I’d have very low expectations for getting clear images of anything at 17 degrees elevation. Even if Jupiter is your ultimate goal, you might try a target at higher elevation to help refine your technique and rule out any equipment issues. Jul 10, 2020 at 12:48

I don’t think it’s any of the points you suggest. The scope and camera are fine for what you are doing.
I’d say that the focus is slightly off. It takes a lot of effort to get it spot on

• This sounds like the beginning of a new question about how to get focus spot-on, better than atmospheric seeing allows, using amateur equipment (rather than a laser/artificial star)
– uhoh
Jul 10, 2020 at 13:28
• @uhoh Use of an LGS won't really help in LuckyImaging, because LGS is intended to help measure the atmospheric distortions, while LI "skirts around" it. However, simply adjusting focus to minimize the image spot size of any actual star in the vicinity of Jupiter's angular position should suffice. Jul 10, 2020 at 16:00
• My instinct was the focus being off. I tried minimizing the spot size of Callisto, Ganymede, and Altair to improve the focus, even hooked up my laptop and ran some point spread minimization to no avail. I tried both using the 'live view' of the camera and iteratively taking a few frames and gently refining the focus -- but every exposure still looks slightly out of focus to me. I'm going to try a Bahtinov mask next week but if that doesn't improve it I'm not sure where to go from here (assuming it is in fact not able to focus correctly). Jul 10, 2020 at 20:25
• Don't yet focus on Jupiter, but use a bright star instead. With my Dslr I set it to video mode then and minimize the star's image. Then I switch back to photo and go to the object of interest Jul 11, 2020 at 0:24
• @WilliamMiller: use a Bahtinov mask to find the focus. The eyes are decpetive, expecially for those of us beyond 40 ;-). Mind moisture that could build up. The 45min cooling time are too short, give it 2 hours. If that doesn't sharpen the image, it's simply atmopsheric conditions that don't allow better results. That happens.
– user34599
Aug 11, 2020 at 12:23