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Need help improving my Andromeda images (DSLR based)


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9 hours ago, INeedSomeHelp said:

 but my internet here is quite bad. 

Plate solving via astrometry.net may not be viable for you then,
so a local platesolve my be better and a lot faster !

One that has helped me find my way pointing my dslr is a neat freeware by 
Giovanni Benintende called All Sky Plate Solver. Here
I think it is only available on Windows though, and as you are using Siril,  not DeepSkyStacker, does this imply you are Linux or Mac ?
It is quite a small download and the index files that also need to be downloaded are quite small for 50mm to 135mm lenses.

Another is ASTAP plate solver which will also run in Linux or so I am told, but I have not got it to sing for me yet ! :(

Good luck with your next outing, I shall be after Andromeda later when it comes into my view.

 

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22 hours ago, Malpi12 said:

Plate solving via astrometry.net may not be viable for you then,
so a local platesolve my be better and a lot faster !

One that has helped me find my way pointing my dslr is a neat freeware by 
Giovanni Benintende called All Sky Plate Solver. Here
I think it is only available on Windows though, and as you are using Siril,  not DeepSkyStacker, does this imply you are Linux or Mac ?
It is quite a small download and the index files that also need to be downloaded are quite small for 50mm to 135mm lenses.

Another is ASTAP plate solver which will also run in Linux or so I am told, but I have not got it to sing for me yet ! :(

Good luck with your next outing, I shall be after Andromeda later when it comes into my view.

 

You are correct in that assumption, I am on mac. I think that I will try and follow your "star hopping" directions as they are really detailed and newbie proof. Thanks for that. Before I start blasting again, do you think that at 100mm, f2.8; 1600 ISO and 3s exposure I can clearly see Andromeda after having followed your hopping pattern?

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23 hours ago, INeedSomeHelp said:

 do you think that at 100mm, f2.8; 1600 ISO and 3s exposure I can clearly see Andromeda after having followed your hopping pattern?

A good question, not sure, I have not yet been able to explore that bit of sky with my camera!
But no I dont think so, not as a smudge of galaxy, however it has a bright core that may appear star-like at around mag4 I think. Certainly you should be able to see mu And., above Mirach and then your target is the same distance the other side of mu.
I2sa.jpg.26d8b648da91f240dce2278b5ac302ad.jpg

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On 25/07/2021 at 18:04, INeedSomeHelp said:

do you think that at 100mm, f2.8; 1600 ISO and 3s exposure I can clearly see

PS !

I should have asked : In  the stacked exposure that you showed us, which of the stars could you see in single exposures at the camera lcd, any ! ?

Ie. what is your light pollution and what ISO can you go up to ?

 

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16 minutes ago, Malpi12 said:

PS !

I should have asked : In  the stacked exposure that you showed us, which of the stars could you see in single exposures at the camera lcd, any ! ?

Ie. what is your light pollution and what ISO can you go up to ?

 

In that image, I could see Alpheratz quite clearly on the LCD. And that was with a full moon behind me. If I took an image with 1600 ISO some other stars also popped up.

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1 hour ago, INeedSomeHelp said:

with 1600 ISO some other stars also popped up.

That is good, you should be ok to follow via delta and mu. Others here who have shot the galaxy should be able to advise on the visibility of the core relative to these stars.

Good luck.

 

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On 24/07/2021 at 20:54, Malpi12 said:

Plate solving via astrometry.net may not be viable for you

astrometry.net is an app which runs natively on Linux. You do not need an Internet connection. Just install the program locally.

Another alternative is Astap. Again standalone.

HTH

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1 hour ago, alacant said:

astrometry.net is an app which runs natively on Linux. You do not need an Internet connection. Just install the program locally.

Another alternative is Astap. Again standalone.

HTH

Thanks for the correction, yes, my bad, I should have said nova.astrometry.net ! 

I did mention ASTAP   & that I was having probs with it (in my windows 64bit).  **  It is also available for Mac and RaspPi.


**edit Update. Working now, I didnt have min and max set right,  doh!

Edited by Malpi12
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On 27/07/2021 at 00:03, Malpi12 said:

Thanks for the correction, yes, my bad, I should have said nova.astrometry.net ! 

I did mention ASTAP   & that I was having probs with it (in my windows 64bit).  **  It is also available for Mac and RaspPi.


**edit Update. Working now, I didnt have min and max set right,  doh!

So I now have repeated this "experiment" and I for sure have found M31 now. The stacking will probably take a full night, but soon I will hopefully have something to show.

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On 23/07/2021 at 18:02, alacant said:

Hi

Really? It looks as if it's been stretched,

Should be easy to diagnose. How about posting -a link to- the .tif or .fits from the Siril working directory? There's only around 10 minutes of exposure, but there maybe something... 

Cheers

I have a new image, much better! I have stacked about 650 light frames in SiriL; I: 1) Applied the automatic Color Calibration (for M31 ofcourse). 2) Corrected the green noise. 3) Exported both a .tif without and one WITH background extraction (2 images are attached). The background extraction (as I understand it) is to get rid of the gradient in background color. In my non-background corrected image you can see that the background at the bottom is quite orange (light pollution from a road I think). The background extraction fixes this quite nicely, BUT it also causes some very heavy graining to occur. 

Lastly I applied the stretching algorithm that is build in in SiriL under "Histogram Transformation" and saved the .tifs as a 16 bit image. I know you can perform manual stretching in Adobe Photoshop but this was quite difficult and since SiriL can do this job for me, with quite good effect, I show my .tifs in this post.

Now I'm curious what to do with that background correction and the graining, and how to proceed in Photoshop! Im already quite happy, you can even see the satellite galaxy.

stretchedwithoutbackgroundcorrection.tif.tif stretchedwithbackgroundcorrection.tif

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