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M57, Short exposures with the logiciel Siril

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#1 exaxe

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Posted 06 February 2018 - 10:48 AM

Hello !

To test this new version of this software,SIRIL, which is really a precious help for short exposures imaging, I chose an old capture of M57 (SER-8b-500ms) that I made in 2016.

It has an option, among others, which is interesting, it's the Drizzle.
Quickly: the Drizzle is a function that allows you to recover information lost / hidden by sub sampling.
The Drizzle works well if there is:
-a number of high frames
-random dithering
-a sub-sampling

And that's exactly the components of deep sky acquisition in fast mode!
We capture thousands of brutes, no autoguiding + a bit of wind + EP and we are under sampled (but not too much anyway).

Moreover, if we associate the deconvolution with the Drizzle we manage to highlight details on these small nebulae more easily than the deconvolution alone.

 

Usual setup:

300mmF4 barlow 2x and asi224mc

acquisitions details:

frames:10000/15000, gain 500, expo:500ms

 

28231531989_39286a752b_c.jpg

 

the FULL

 

And a comparison with the big one in space to just see if my details are not artifacts...

CZ6hiHgHNUD28ut38LFNyS428zA.gif

 

Stephane Go


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#2 calypsob

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Posted 06 February 2018 - 11:00 AM

Nice work Stephane, what a huge effort.  The resolution you have a achieved is impressive.  I would be curious to see what this data looked like if combined with some long exposures.  



#3 exaxe

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Posted 06 February 2018 - 11:09 AM

thank you Calypsob, hybridization between long and fast poses would really be the best solution.
The future is at the blend!



#4 schmeah

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Posted 06 February 2018 - 11:18 AM

Stunning. The fine detail is absolutely amazing. Congrats!

 

Derek



#5 exaxe

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Posted 06 February 2018 - 11:36 AM

thank you Derek



#6 Roberto Marinoni

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Posted 06 February 2018 - 12:02 PM

Impressive details!



#7 jhayes_tucson

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Posted 06 February 2018 - 12:44 PM

Stephane,

This is a really impressive result!  I'm also impressed that you gathered 15,000 subs.  That's a lot of data.  I think that you are on the leading edge of what is possible with a small telescope.  Very well done!

 

John



#8 GA-HAMAL

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Posted 06 February 2018 - 03:54 PM

 

To test this new version of this software,SIRIL, which is really a precious help for short exposures imaging

 

Wow!  smile.png  I will have to try this program.



#9 exaxe

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Posted 06 February 2018 - 03:55 PM

thank you Roberto

thank you John

thank you Ga-Hamal



#10 nmoushon

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Posted 06 February 2018 - 06:01 PM

This is great work! 

 

Do you think the fast f/ratio plays a big role in the success of short exposure? Or would a slower ratio work just as well, with in mind that you would need more total integration time.



#11 exaxe

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Posted 07 February 2018 - 01:33 PM

thank you Nmoushon,

I think the exposure should be as short as possible with as little sampling as possible. To compensate for the lack of light, you need a maximum of frames.




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