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Jupiter, 19th Sept am.


symmetal
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First time planetary for this year with the LX200GPS, 2x Powermate, Zwo ADC, ASI224MC. Found the collimation was way out, possibly due to the wild temperature changes in the shed up to 45C in summer even though there is an extractor fan which comes on at 20C. All the weather satellite receivers and processing PCs in the shed give out a fair amount of heat. The spiders don't mind the heat though as it's like a scene from Aracnophobia when you open the shed. Had to disconnect several large web anchors from the scope before wheeling it outside causing a bit of a scuttling frenzy. 😬

Took several videos near the Meridian of various lengths and exposures. Found 5mS for 30 seconds gave the sharpest result. 45s and 60 secs were noticeably softer though it was likely the focus drifting. Others at 2 to 4mS were softer too so must remember to check focus more often.

Anyway here's the sharpest result. 5mS exposure, 30 secs video at 200fps. Stacked in AS3 using 15% (900 frames). 5 and 10% were sharper but more noisy. Wavelets in Registax 6. Colour and slight curves adjustment in Photoshop.

50474030_Jupiter2022-09-20-00185.0mS_900frames.png.4bcf928a044591b6283ef48d1b6f7715.png 

Alan

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55 minutes ago, symmetal said:

First time planetary for this year with the LX200GPS, 2x Powermate, Zwo ADC, ASI224MC. Found the collimation was way out, possibly due to the wild temperature changes in the shed up to 45C in summer even though there is an extractor fan which comes on at 20C. All the weather satellite receivers and processing PCs in the shed give out a fair amount of heat. The spiders don't mind the heat though as it's like a scene from Aracnophobia when you open the shed. Had to disconnect several large web anchors from the scope before wheeling it outside causing a bit of a scuttling frenzy. 😬

Took several videos near the Meridian of various lengths and exposures. Found 5mS for 30 seconds gave the sharpest result. 45s and 60 secs were noticeably softer though it was likely the focus drifting. Others at 2 to 4mS were softer too so must remember to check focus more often.

Anyway here's the sharpest result. 5mS exposure, 30 secs video at 200fps. Stacked in AS3 using 15% (900 frames). 5 and 10% were sharper but more noisy. Wavelets in Registax 6. Colour and slight curves adjustment in Photoshop.

50474030_Jupiter2022-09-20-00185.0mS_900frames.png.4bcf928a044591b6283ef48d1b6f7715.png 

Alan

 Hi Alan unsure why you are limiting your time frame so drastically. Even 3 minuets only produce a very slight softening. Which is more than made up from the benefit of six times the number of frames to work with. Even a conservative 2 mins the softening will be very minimal. Just unsure what you expect to achieve by cutting the captures back so drastically.You mention focus is the primary drifting ? But to play devil's advocate I will run some experiments and compare outcomes at some point. But to be honest it's already been done. See underneath. Do you not use winjupos ?  Aside from that Nice capture. Cant wait to get back out there. As Jupiter is now big and bright approaching opposition.  Weather has been very unpredictable lately. Too risky without a obs

juprotate3mnWJAS.gif

Edited by neil phillips
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40 minutes ago, neil phillips said:

Hi Alan unsure why you are limiting your time frame so drastically.

Hi Neil. I did take videos of 1 min and 2 mins as well to do some comparisons, but I think the focus must have shifted as every stacked video after this first 30 sec one was noticeably softer so I just went with the sharpest image before using Registax. 🙂

I'll have another go if it's clear and do a focus check more often. The scope had been outide for 4 hours in the dark beforehand so assumed it had stabilized. I did readjust the ADC slightly at one stage. I had checked before with a bahtivov mask on a star and moving the ADC levers didn't seem to affect focus which surprised me but maybe I need to check more closely.

I have used WinJupos in the past and it did improve the image a little but it takes a bit more dedication to use it. 😁

Alan

Edited by symmetal
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56 minutes ago, symmetal said:

Hi Neil. I did take videos of 1 min and 2 mins as well to do some comparisons, but I think the focus must have shifted as every stacked video after this first 30 sec one was noticeably softer so I just went with the sharpest image before using Registax. 🙂

I'll have another go if it's clear and do a focus check more often. The scope had been outide for 4 hours in the dark beforehand so assumed it had stabilized. I did readjust the ADC slightly at one stage. I had checked before with a bahtivov mask on a star and moving the ADC levers didn't seem to affect focus which surprised me but maybe I need to check more closely.

I have used WinJupos in the past and it did improve the image a little but it takes a bit more dedication to use it. 😁

Alan

Ahh ok think that makes more sense now. Sometimes temperature changes can shift focus slightly. As can atmosphere changes. And seeing going soft. I've seen it myself often.  As long as you're sure the SCT primary isn't drifting. Clearly if you get a longer more stable run. You're in for a treat. Because with such a short capture it's looking pretty darn good. Your technique might work better for you of course. But personally, I wouldn't trust such critical focusing as planetary detail using a mask. I've seen changes of the focuser like 4 or 5mm turns or less. Produce huge sharpening effects on the image. Really slight turns. Its great practice to get your eyes on this procedure. After a while you get to see when all the fine detail starts coming out. with a slight tunning of the focuser. When your eye sees it. it stops you in your tracks so to speak literally. Right before you hit capture. Anyway. Good result. I like your minimalist processing. Sometimes we do too much.

Edited by neil phillips
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@neil phillips Thanks. It might be worth bracketing the initial exposures with focus so see which one is best but that means stacking each exposure which takes some time. Probably worth it to save a lot of potentially soft videos. Also repeat every 30 mins or so. Using a bahtinov mask to mentally integrate a collection of a few seconds worth of exposures and determine the average is a bit of a challenge which I have yet to master. 🙂

@Kon Thanks. Yes the seeing was pretty good as the video image wasn't dancing around much during capture. 🙂

@CraigT82 Thanks. My monitors aren't colour calibrated so it's quite likely off colour. 😉 I'm not sure what colour Jupiter should be so choose what makes it look pretty. 😊

If anyone wants to have a go at processing it, here's the stacked tif from Autostakkert3

2022-09-20-0018_5-U-RGB-ZWO ASI224MC_Gain=350(off)_Exposure=5.0ms_4_Jup_lapl4_ap330.tif

Alan

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43 minutes ago, CraigT82 said:

Nice one, love playing with other peoples data... good practice!  Here's my attempt, using Astrosurface and Gimp.

11 minutes ago, neil phillips said:

Pushed it as much as I could without artifacts. Its good data

Like both your versions. Thanks. In comparison mine is a bit green. You've avoided the curved artifact on the left edge which I have. Will have to look into Astrosurface. 😉

Alan

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1 minute ago, symmetal said:

Like both your versions. Thanks. In comparison mine is a bit green. You've avoided the curved artifact on the left edge which I have. Will have to look into Astrosurface. 😉

Alan

Didnt avoid it Alan. I blurred it away. Its false so I have no problem removing false data. 

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Yeah I used an inverted elliptical selection and applied a slight Gaussian blur to the edge of the disk (in gimp). Sorts out the ghosted limb and just gives a bit more of a natural looking disk. 

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Just now, CraigT82 said:

Yeah I used an inverted elliptical selection and applied a slight Gaussian blur to the edge of the disk (in gimp). Sorts out the ghosted limb and just gives a bit more of a natural looking disk. 

Its the little things that make a whole. worth doing Craig. I used photoshop. different process same result. Both look good

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1 hour ago, neil phillips said:

Its the little things that make a whole. worth doing Craig. I used photoshop. different process same result. Both look good

Indeed! Always good to share the little tricks of the trade 

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@Laurieast Thanks, you've accentuated some detail there Laurence. 🙂 If you're using Registax wavelets, then the noise reduction parameter associated with each slider, particularly the top slider is good at mitigating the noise mottling effect. 

Alan

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19 hours ago, symmetal said:

If you're using Registax wavelets, then the noise reduction parameter associated with each slider, particularly the top slider is good at mitigating the noise mottling effect. 

A bit less motley 😉 

 

image.png.9a39e2b0d39d87b3840fecfde5402d2b.png

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As it's cloudy I've had another go, this time I made use of the Wiener deconvolution function in Astrosurface. Tried to define the detail whilst maintaining smoothness.

First attempt left, latest right.

Thanks again for sharing your data @symmetal. If I ever get around to capturing anything this apparition I’ll be sure to share it too! 

2022-09-20-0018_5-U-RGB-ZWO ASI224MC_Gain=350(off)_Exposure=5.0ms_4_Jup_lapl4_ap330_CT new.png

Edited by CraigT82
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2 hours ago, CraigT82 said:

As it's cloudy I've had another go, this time I made use of the Wiener deconvolution function in Astrosurface. Tried to define the detail whilst maintaining smoothness.

First attempt left, latest right.

Thanks @CraigT82 for your latest attempts, certainly smooth with good detail. 🙂

I was wondering if you or the others, as an exercise, would like to try with different stack percentages to see if more stacked frames allows you to extract more detail despite it being slightly softer initially. I've zipped up a collection of 5%, 10%, 20%, 25%, 30%, 40% and 50% stacks ranging from 300 to 3000 stacked frames. The seeing was good as the AS3 graph indicates so even 50% stack has no frames below average. The one you've already processed was 15%.

1101060884_4graph.png.d7e1915c8947c8848caa2ce1954eb850.png

2022-09-19, Jupiter.zip

Alan

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I've had a go at your 300 and 3000 frame stacks, just to see the difference that ten times the frames gives you.  Same processing in Astrosurface (I applied the processes to the 3000 frame image first then applied that same process to the 300 frame). No other post processing or touching up applied, not even any noise reduction.

 

300 frame on left, 3000 on right

300 vs 3000 frames CT.png

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52 minutes ago, CraigT82 said:

I've had a go at your 300 and 3000 frame stacks, just to see the difference that ten times the frames gives you.  Same processing in Astrosurface (I applied the processes to the 3000 frame image first then applied that same process to the 300 frame). No other post processing or touching up applied, not even any noise reduction.

That's quite impressive Craig. You don't actually need a very large number of frames to get a good image. The 300 stack is of course more noisy which is giving the initial impression it's a sharper image, but more detail is certainly revealed in the lower contrast areas in the 3000 stack, even though the initial image was softer. I'll try 1 min and 2 min videos next time as well, tring to ensure the focus is good. 😀 Tomorrow is currently showing geen.

Alan

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On 21/09/2022 at 02:56, symmetal said:

Hi Neil. I did take videos of 1 min and 2 mins as well to do some comparisons, but I think the focus must have shifted as every stacked video after this first 30 sec one was noticeably softer so I just went with the sharpest image before using Registax. 🙂

I'll have another go if it's clear and do a focus check more often. The scope had been outide for 4 hours in the dark beforehand so assumed it had stabilized. I did readjust the ADC slightly at one stage. I had checked before with a bahtivov mask on a star and moving the ADC levers didn't seem to affect focus which surprised me but maybe I need to check more closely.

I have used WinJupos in the past and it did improve the image a little but it takes a bit more dedication to use it. 😁

Alan

Bit late to the party, but I’ve often found that with more frames it may look softer pre sharpening. When you take it into registax however, you can push it much more without having to denoise in response, ending up with the better image. I’m not super experienced, so Neil and co.‘s advice is more important, but this may at least explain why you were seeing the difference pre registax. 

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4 hours ago, sorrimen said:

Bit late to the party, but I’ve often found that with more frames it may look softer pre sharpening. When you take it into registax however, you can push it much more without having to denoise in response, ending up with the better image. I’m not super experienced, so Neil and co.‘s advice is more important, but this may at least explain why you were seeing the difference pre registax. 

@sorrimen Hi. I agree that pre sharpening it's difficult to spot any difference between the stacks but I did apply the same wavelet enhancement to each stack and then compared the results and the difference between them was much more apparent then. 🙂

Alan

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