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Can someone have a look at my Jupiter stack?

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#1 Jay6879

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Posted 06 August 2022 - 11:45 AM

The last time I did any planetary imaging was years ago, now here I am with my Skymax 150 and brand new asi585. Last night the conditions were surprisingly good so I figured let's give it another shot.

 

I stacked it in AS3, went into registax excited to see what it would look like and...I was very disappointed. Moving the sliders around and all that was there was a mess. I have images from years ago using a manual starblast 4.5 with a 2x barlow stacked on a 3x barlow that looked better than this. To say I was dejected is an understatement, little detail visible on Jupiter. Some muddled cloud bands sure but not much else. Judging by some of the images in the small bore thread there is a ton more potential here.

 

Can someone have a look at the final stack and let me know what I'm doing wrong in processing? Or in the capturing part? I need guidance! 

 

This is the final stack, no other processing yet.

 

https://www.dropbox....5_ap58.tif?dl=0


Edited by Jay6879, 06 August 2022 - 11:46 AM.


#2 randcpoll

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Posted 06 August 2022 - 11:54 AM

Probably your focusing needs improvement. Either that or you have some very bad local air instability due to heat coming off concrete or a nearby building.



#3 RedLionNJ

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Posted 06 August 2022 - 12:40 PM

That's definitely a tiny Jupiter.  Overall, it's kind of hard to tell what the issue may be, other than image scale. Here's my quick process in R6.  There is definitely some detail visible, and I had to adjust the color plane alignment (no ADC, I assume?). There's definitely a ton more potential, as you put it. Are you trying to focus with the stock primary-moving focuser?  How about an IR-cut filter?

 

I'm not sure how long you let your equipment cool (or heat up) to reach ambient, but I'd be allowing at least 45 minutes this time of year.

 

The 2.9 micron pixels of the 585 could probably benefit most from an f-ratio in the f/15-f/20 range. What were you operating at? Native f/12?  That's not SO far off, but I can't help thinking the resulting image is just too small for that kind of f-ratio. Most peculiar.

 

 

00_54_09_lapl5_JPG.jpg

 

 

58 alignment points on a Jupiter this small and 'soft' doesn't make a lot of sense to me, either. No more than a dozen would be more appropriate.

 


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#4 Sky King

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Posted 06 August 2022 - 12:50 PM

Hard to say what went wrong, try again, you'll get there!

 

Brand new gear needs explored, different gain, focus, etc. 

 


Edited by Sky King, 06 August 2022 - 01:15 PM.

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#5 dswtan

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Posted 06 August 2022 - 01:17 PM

Similar here. Sharing settings. This is exactly what I would expect to get with my local seeing and a 6" scope. Keep going!

 

  • My RS6 version
  • Your original
  • Settings (and also some manual RGB alignment + Auto RGB balance

 

00 54 09 lapl5 ap58 Rs6
 
00 54 09 lapl5 ap58 copy
 
00 54 09 lapl5 ap58 rs6.rwv

 


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#6 Jay6879

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Posted 06 August 2022 - 04:03 PM

That's definitely a tiny Jupiter.  Overall, it's kind of hard to tell what the issue may be, other than image scale. Here's my quick process in R6.  There is definitely some detail visible, and I had to adjust the color plane alignment (no ADC, I assume?). There's definitely a ton more potential, as you put it. Are you trying to focus with the stock primary-moving focuser?  How about an IR-cut filter?

 

I'm not sure how long you let your equipment cool (or heat up) to reach ambient, but I'd be allowing at least 45 minutes this time of year.

 

The 2.9 micron pixels of the 585 could probably benefit most from an f-ratio in the f/15-f/20 range. What were you operating at? Native f/12?  That's not SO far off, but I can't help thinking the resulting image is just too small for that kind of f-ratio. Most peculiar.

 

 

attachicon.gif00_54_09_lapl5_JPG.jpg

 

 

58 alignment points on a Jupiter this small and 'soft' doesn't make a lot of sense to me, either. No more than a dozen would be more appropriate.

 

For this particular stack yes I was at the native f12, 640x480 roi. My equipment was outside for a few hours before using it, and no adc. As for the alignment points to be honest injust left it at the default size (32) and let it add them automatically. Should I be doing this manually?

 

What was shocking to me is a few years ago I used a $300 tabletop dob (Starblast 4.5), a neximage burst and a 2x barlow stacked ON TOP of a 3x barlow and managed this.. 

 

Jupiteraug7x6longv2.jpg

 

So you can understand my shock when I saw what I got out of this much higher end equipment!


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#7 RedLionNJ

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Posted 06 August 2022 - 04:10 PM

 

attachicon.gifJupiteraug7x6longv2.jpg

 

So you can understand my shock when I saw what I got out of this much higher end equipment!

Equipment, while definitely a factor, comes after seeing and (usually) processing experience.

 

When the seeing is really, genuinely excellent, everything else just sort of falls into place.


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#8 Jay6879

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Posted 06 August 2022 - 04:58 PM

Equipment, while definitely a factor, comes after seeing and (usually) processing experience.

 

When the seeing is really, genuinely excellent, everything else just sort of falls into place.

 

In your opinion you think the seeing was just no good? That's why it's a mushy mess? I guess that doesn't explain the small planet though..

 

I appreciate everyone's input. Not sure how to move forward here (especially with the dinky planet size) but I'll be out to try again, hopefully with better seeing!

 

 

 


Edited by TimN, 07 August 2022 - 05:17 AM.


#9 CrazyPanda

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Posted 06 August 2022 - 10:50 PM

In your opinion you think the seeing was just no good? That's why it's a mushy mess? I guess that doesn't explain the small planet though..

 

Seeing is really a killer. Not only does the seeing itself cause problems, it also makes it impossible to get accurate focus, which is a double-whammy.

 

The small planet is just a matter of imaging at the appropriate focal ratio for your camera and the atmospheric conditions.

 

Generally speaking, when it comes to Jupiter, you should expect Jupiter to be about the same number of pixels as your aperture (maybe a bit more, up to a factor of 1.2). A 150mm aperture should result in about a 150-180 pixel Jupiter. Somewhere in that range would be adequate sampling for any given camera. The image you found is 165 pixels, which is in line with someone who used an appropriate focal length / focal ratio for a 150mm scope.

 

So I would say the first order of business is to set your expectation there. Your small capture just means you were under-sampled. I measure your Jupiter to be 127 pixels across. If you get a 2x barlow with a detachable lens cell, and you thread that lens cell directly to the nose piece of your camera, you will wind up with something like a 1.3x to 1.5x barlow. That will give you an appropriate focal ratio for your camera, and the image scale that would match the image you found.

 

From there, it's a matter of atmospheric conditions, a telescope that's thermally acclimated, good focus, and data. Lots and lots and lots of data.

 

Seeing is going to be the biggest limit. Don't get discouraged. Some nights will have atrocious seeing, others will have very good seeing. You just have to go out and capture data and hope you get lucky, and don't fret if 95% of the data you capture is junk. High resolution planetary imaging is very demanding of the atmosphere.


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#10 Jay6879

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Posted 07 August 2022 - 10:05 AM

Seeing is really a killer. Not only does the seeing itself cause problems, it also makes it impossible to get accurate focus, which is a double-whammy.

 

The small planet is just a matter of imaging at the appropriate focal ratio for your camera and the atmospheric conditions.

 

Generally speaking, when it comes to Jupiter, you should expect Jupiter to be about the same number of pixels as your aperture (maybe a bit more, up to a factor of 1.2). A 150mm aperture should result in about a 150-180 pixel Jupiter. Somewhere in that range would be adequate sampling for any given camera. The image you found is 165 pixels, which is in line with someone who used an appropriate focal length / focal ratio for a 150mm scope.

 

So I would say the first order of business is to set your expectation there. Your small capture just means you were under-sampled. I measure your Jupiter to be 127 pixels across. If you get a 2x barlow with a detachable lens cell, and you thread that lens cell directly to the nose piece of your camera, you will wind up with something like a 1.3x to 1.5x barlow. That will give you an appropriate focal ratio for your camera, and the image scale that would match the image you found.

 

From there, it's a matter of atmospheric conditions, a telescope that's thermally acclimated, good focus, and data. Lots and lots and lots of data.

 

Seeing is going to be the biggest limit. Don't get discouraged. Some nights will have atrocious seeing, others will have very good seeing. You just have to go out and capture data and hope you get lucky, and don't fret if 95% of the data you capture is junk. High resolution planetary imaging is very demanding of the atmosphere.

 

Ok, so I gotta just keep forging ahead eh and understand that seeing is number one. Work on my focus and try to get to around 1.5x native focal length. I have an older Celestron SV Ultima that DOES unscrew...unfortunately it doesn't screw into the nosepiece of the camera! It just sits flush. Do you know of an adapter that would screw into the nosepiece then allow the barlow to be screwed into the adapter? If not I may have to do some research into what barlows can be unscrewed like that.

 

Another factor I'm sure is that the planets are still quite low. I'm at 44° so there is still a month or so before planets are prime.

 

I appreciate the encouragement and info, 



#11 CrazyPanda

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Posted 07 August 2022 - 10:19 AM

Ok, so I gotta just keep forging ahead eh and understand that seeing is number one. Work on my focus and try to get to around 1.5x native focal length. I have an older Celestron SV Ultima that DOES unscrew...unfortunately it doesn't screw into the nosepiece of the camera! It just sits flush. Do you know of an adapter that would screw into the nosepiece then allow the barlow to be screwed into the adapter? If not I may have to do some research into what barlows can be unscrewed like that.

 

Another factor I'm sure is that the planets are still quite low. I'm at 44° so there is still a month or so before planets are prime.

 

I appreciate the encouragement and info, 

Too bad about that barlow not having the right size/threads to screw into the nosepiece. There are a number of barlows with threaded lens cells. There's also the option to add the Vernonscope Brandon Magic Dakin barlows (1.5x and 1.25x). These should screw into any standard 1.25" nosepiece that accepts common filters (which the ZWO camera nosepieces do).

 

The Celestron Omni barlow may work (not entirely sure though - a few of those Amazon reviews confirm you can do it), and it's currently on sale: https://www.amazon.c...s/dp/B00008Y0TM


Edited by CrazyPanda, 07 August 2022 - 10:21 AM.

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#12 Jay6879

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Posted 09 August 2022 - 01:12 PM

Too bad about that barlow not having the right size/threads to screw into the nosepiece. There are a number of barlows with threaded lens cells. There's also the option to add the Vernonscope Brandon Magic Dakin barlows (1.5x and 1.25x). These should screw into any standard 1.25" nosepiece that accepts common filters (which the ZWO camera nosepieces do).

 

The Celestron Omni barlow may work (not entirely sure though - a few of those Amazon reviews confirm you can do it), and it's currently on sale: https://www.amazon.c...s/dp/B00008Y0TM

 

Ehhh the reviews and pictures on there put me off. Quite a few claims of counterfeit products, item looks different than what is on the Amazon page, all the way to some people apparently receiving just empty tunes haha.

 

I'm going to order a GSO 2x 1.25" barlow. Those are advertised as having a removable lens cell, and apparently they're pretty decent for the price?




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