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Old 13-06-2021, 07:05 PM
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toc (Tim)
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Luckyimaging technique...

Might have to give this technique a go:
https://www.youtube.com/watch?v=4rCy...l=Astrobiscuit

He doesn't mention what tools are used to stack so many images, but I believe Siril can do it.

I guess Sharpcap live stacking might also work? (and would save on having to store 5000 images or more)
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Old 13-06-2021, 08:17 PM
sunslayr (David)
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This is a nice guide to get you started. I believe this chap gets most of his images using lucky imaging, if you want to see what its capable of. You really want one of those nice new low noise cameras from ZWO and QHY to get the most out of it. I think my 1600mm has a better signal to noise ratio at around 30s rather than 5 or 10. Could make the difference on those really faint fuzzies.
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Old 14-06-2021, 09:04 AM
Alchemy (Clive)
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Stacking 1000 images is mind boggling, although the suggestion is to do them in smaller batches.
Of note a rasa f2 collects about 15 times the light as f7 so a 10 sec f2 is similar to 150 sec f7 give or take. So i can see how this could work.

Did watch the video listed, quite entertaining, I do love the concept, it’s a 700 quid scope but I’ve spent many many hours fixing it. ( apparently time has no $ value here), the more mature gentleman’s response to cutting the tube… glad he left that in, very honest approach.
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Old 14-06-2021, 10:16 AM
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Because I had difficulties getting a very decent polar alignment at first and later various teething problems with my auto guiding I found I was going for very short exposures and also very high gain ( more than one should use)... Short exposures became the norm, 30 seconds up to 90 seconds but at some point I seemed to find I would go for 45 to 60 seconds. And gain ( zwo 1600 mono) up to 450 for HA but finally this settled at 250 to 350...all way way past where one should be... And still no darks or flats so within this approach there is room for improvement by incorporating darks and flats...however I do two things...cull any sub that is not great and stack heaps...Often I stack 500 but have stacked just under 700 and some of these I have used "drizzle" which I feel improves my result...but a huge stack and 3 times drizzle has the computer going all night...I use Startools which really seems to tidy up the noise...to me the results are acceptable but probably would draw negative comments from folk more skilled...but I am happy and really thats all I care about.
Because I am colour blind my asperations are low...that will always hold me back so I dont get too serious.
I have a RASA 11 inch coming and a ZWO mono 2600 which I plan to explore short exposures with...my belief is the shorter the exposures the more you will pick and choose and I guess I have developed a similar philosophy to the guy making the video in that you will get both good and bad moments of seeing..just pick 1000 good ones to stack
Here is a Lagoon captured with short exposures and high gain that I have been playing with..I realise it is off in many aspects, particularly colour but I think the detail is not too bad...which is what I look for..anyways this turned out better than the one I did using 2 minute exposures, which I have lost otherwise would post it to compare.
Alex
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Old 14-06-2021, 11:40 AM
Startrek (Martin)
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Originally Posted by xelasnave View Post
Because I had difficulties getting a very decent polar alignment at first and later various teething problems with my auto guiding I found I was going for very short exposures and also very high gain ( more than one should use)... Short exposures became the norm, 30 seconds up to 90 seconds but at some point I seemed to find I would go for 45 to 60 seconds. And gain ( zwo 1600 mono) up to 450 for HA but finally this settled at 250 to 350...all way way past where one should be... And still no darks or flats so within this approach there is room for improvement by incorporating darks and flats...however I do two things...cull any sub that is not great and stack heaps...Often I stack 500 but have stacked just under 700 and some of these I have used "drizzle" which I feel improves my result...but a huge stack and 3 times drizzle has the computer going all night...I use Startools which really seems to tidy up the noise...to me the results are acceptable but probably would draw negative comments from folk more skilled...but I am happy and really thats all I care about.
Because I am colour blind my asperations are low...that will always hold me back so I dont get too serious.
I have a RASA 11 inch coming and a ZWO mono 2600 which I plan to explore short exposures with...my belief is the shorter the exposures the more you will pick and choose and I guess I have developed a similar philosophy to the guy making the video in that you will get both good and bad moments of seeing..just pick 1000 good ones to stack
Here is a Lagoon captured with short exposures and high gain that I have been playing with..I realise it is off in many aspects, particularly colour but I think the detail is not too bad...which is what I look for..anyways this turned out better than the one I did using 2 minute exposures, which I have lost otherwise would post it to compare.
Alex
Alex
I agree totally with shorter subs and more of them
You lower the risk to your subs for tracking error, guiding error , wind gusts , seeing and transparency conditions , satellite trails , passing cloud etc.... and can still process good images, you just need lots of data
Great detail by the way on your M8 , proof that it actually works ......
Some of my best images have come from shorter guided subs ( 90 sec to 3 minutes ) IMO unless you have a +$7K mount ( most of us don’t ) and want to go really deep with the longer focal length rigs, 5 to 10 minute subs or longer are too risky and totally dependent on atmospheric conditions
I’m imaging at 1000mm and 90 sec to 3 minutes works well amongst the objects that I image , if conditions are really good I might go 5 minute but that’s on rare occasions
There’s a guy in Japan who has a YouTube channel ( Cuiv the lazy geek ) and he images galaxies under Bortle 9 , takes hundreds of 60 sec and 90 sec subs just using a Luminance filter and produces absolutely incredible Galaxy images

Cheers
Martin
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Old 14-06-2021, 12:20 PM
Alchemy (Clive)
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Quote:
Originally Posted by xelasnave View Post
Because I am colour blind my asperations are low...that will always hold me back so I dont get too serious.
Alex
Guy who taught me my trade was colour blind, he lined up a bunch of green and red things thinking they were brown,

You tried the Enchroma glasses….. ?
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Old 14-06-2021, 12:58 PM
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Guy who taught me my trade was colour blind, he lined up a bunch of green and red things thinking they were brown,

You tried the Enchroma glasses….. ?
Not yet but I plan doing something. I am going to the optometrist and see if they can build me some rather flash glasses that beat the colour blindness and have xray vision.

I see colour but have trouble with red which means blue and purple appear the same, green and brown I have trouble with and I cant see through walls.

But it is not black and white and I am sure that I see detail better than most folk.
Anyways it does not worry me in the least and probably is a good thing else I am sure I would be obsessive with astro photography...Folk dont realise as I hide it consciously but I underneath what I hope appears a slack outer shell I am somewhat a perfectionist, or I was, I think I have it under control these days, I will not worry about spelling or grammatical stuff and let stuff go without many edits or re writing over and over...I have not worn starched under wear for some time now, well of course I will if going shopping as does everyone else no doubt...but at home never on the weekend...
Alex
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Old 14-06-2021, 01:23 PM
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IMO unless you have a +$7K mount
I ordered the RASA 11 planing on using it on the EQ6 and I am reasonably confident it will handle short exposures but I feel I may get a EQ8...it started just getting the mount ..around $6k,.no tripod..but then I thought fitting it to the current pier will be work that I would be best avoiding so go for one with a tripod...so up from about $6 k to $8 k ( approximations only as I dont have to be exact for the story) ...then I notice that there is a $12 k unit..with an encoder..and heck Dillon has one so...I ask John at Bintel to tell me all about it and he says maybe consider the Paramount ...mmmm...add a tripod and what started as $6 k is now $16 k and although I could get my hands on the cash and cant take it with me there is no way I can spend $16 on a mount..would not matter if I had millions in my sock...but it makes the $8 k one seem somehow " thrifty" so maybe ...it depends if I can get back to living in the van...but the EQ 8 appeals in so far as in the future , if there is one, I could get a long fl Celestron 11 inch and get into galaxies down the track ...maybe the $12 one..mmm even the $16 k one ... It is all so stupid really given my current gear is beyond my ability...maybe buy the sports car instead.
Thats the thing when you see what you can buy with the money you can spend on astro gear....
And your lazy geek guy..I like..thanks.
Alex
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Old 14-06-2021, 02:06 PM
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Alex
The RASA 11” is 19.5kg and 800mm long
Add imaging gear ( no guiding )total weight should be around 22 to 23kg max
If well balanced and no wind around the EQ6-R mount should be ok with 22 or 23kgs on board with short exposures ( 60sec )
The EQ6-R is very capable mount
I can’t understand why Skywatcher made a huge jump from the EQ6-R ( 20kg class ) to the EQ8-R ( 50kg observatory class ) and nothing in between
If they made a 30 or 32kg class mount , I’d buy 2 tomorrow ( I’d call it an EQ7-R mount )
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Old 14-06-2021, 02:30 PM
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I'm one of the people managing the project at the end of that video, he set a goal post of better than 2.5 arc second FWHM to score subs and chose his exposure lengths to be around that margin (don't have the exact number)
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Old 15-06-2021, 09:56 AM
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So is it feasable to do this in Sharpcap with its live stacking? I know it does have a FWHM setting which would only stack images that meet a certain threshold.
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Old 15-06-2021, 11:04 AM
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So is it feasable to do this in Sharpcap with its live stacking? I know it does have a FWHM setting which would only stack images that meet a certain threshold.
Try it.,.I certainly will when I am able...can you set gain and exposure....I expect you can...so 5 seconds and a high gain and keep only best 10% maybe and just let it run until it stops or the Sun rises.

And Martin if you are still there...the producer of the video sure backs up our support for the humble 6 inch Newtonian.

Alex
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Old 15-06-2021, 11:06 AM
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I'm one of the people managing the project at the end of that video, he set a goal post of better than 2.5 arc second FWHM to score subs and chose his exposure lengths to be around that margin (don't have the exact number)
I think it was covered in the video but could you post a link please.
Alex
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Old 15-06-2021, 11:58 AM
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Not sure how it plays with the site rules so didnt link before.

The Big Amateur Telescope Project at the end, its not started just yet. As wanted to give time for interested people to join.
https://discord.gg/zcppbhcPHT

Or for the specific parts of the video he mentions the project after 25:11 (original posters link)

https://www.astrobiscuit.com/deepspaceluckyimaging
After i messaged him he has updated his site with how long he was imaging (1200x 5 second frames)
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Old 15-06-2021, 01:07 PM
sunslayr (David)
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I think another approach would be to use N.I.N.A to take 5 or 10 second exposures and include the HFR and number of detected stars in the file name. Then just have a script that automatically deletes exposures that don't meet a threshold.
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Old 15-06-2021, 02:25 PM
Startrek (Martin)
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Originally Posted by xelasnave View Post
Try it.,.I certainly will when I am able...can you set gain and exposure....I expect you can...so 5 seconds and a high gain and keep only best 10% maybe and just let it run until it stops or the Sun rises.

And Martin if you are still there...the producer of the video sure backs up our support for the humble 6 inch Newtonian.

Alex

Alex,


Thanks , I suspect I'm one of a very small number of folk who started out in AP with a basic 6" newt and still use it years later........... Most beginners opt for the popular ED80 or smaller refractors which is fine and then advance to either bigger refractors or SCT's , RC's or RASA's etc..
Ive also had my 8" newt for a few years now , next year going for the 10"

Love Newts

Martin
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