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Excited Over My Attempt On M31


Pankaj

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Hi Everyone

This is my 2nd attempt on M31. Shot through the economical achromat Orion ST 80A on NEQ6 Pro. I know, technically the photograph may not be perfect, but for a newbie like me, the photograph was really rewarding. This is an integrated exposure time of 52 minutes with 4 dark frames and 4 bias framed stacked in DSS. I was so excited when the stacked image popped on the screen. It almost filled the entire FOV. Later I did some post processing in Lightroom, being careful not to tamper the original data much.

One more thing I realized while attempting in this photo. That is, how correct it is when we say, that dark skies matter a ton. I took this photograph from a hill station in the Indian Himalayas called Mukteshwar in the state of Uttarakhand. The sky was absolutely clear and the M31 was visible to naked eye. 

I would really welcome suggestions on how to improve and take better image using the same scope i.e. ST 80A. Please please advice......looking forward...

Regards

Pankaj

post-38054-0-62739800-1452412602.jpg

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That's a great shot Pankaj.

Thanks Dave. 

Would appreciate suggestions if further improvements can be done the next time when I shoot....with the same set up. I.e. Canon 1200D Unmodded at prime focus with ST 80A on NEQ6 PRO.

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Hi Pankaj

That M31 looks like it has a lot of promise! You're right about dark skies - something most of us can only dream about! I'm sure you're image could be much improved with better processing. Not sure if you stacked in dss? You can use various stacking algorithms to improve the signal/noise. Also, there is the option to align the histogram after stacking, and increase saturation to much improve colour. The ST80 is a good little scope but it is an achromat with strong coma. Coma can be improved using the Startools lens function. Startools is free to download but doesn't let you save until you get a paid version (about Australian $50, I think) . Startools has lots of image processing functions. It's a good idea to take flats too. Also, you should think in terms of >20 calibration frames.

Louise

Edit:

Here's a quick and dirty reprocess of your .jpg in Paint.net:

post-33532-0-52770900-1452427008.jpg

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Thanks Dave. 

Would appreciate suggestions if further improvements can be done the next time when I shoot....with the same set up. I.e. Canon 1200D Unmodded at prime focus with ST 80A on NEQ6 PRO.

Well done Pankaj.

I suppose longer exposures will get better detail and SNR, 221sec subs are'nt very

long, especially if you have a dark sky.

I see the cores are burntout, may be thats just the processing, wonder what ISO you were using?

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Well done Pankaj.

I suppose longer exposures will get better detail and SNR, 221sec subs are'nt very

long, especially if you have a dark sky.

I see the cores are burntout, may be thats just the processing, wonder what ISO you were using?

Hi. I was clicking at IS0 400. Should I try doing it at 200, keeping lengthy exposures. But then how do I prevent the core burning out. The same happens with M42. The trapezium area burns out on longer exposures at ISO 400

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Hi Pankaj

That M31 looks like it has a lot of promise! You're right about dark skies - something most of us can only dream about! I'm sure you're image could be much improved with better processing. Not sure if you stacked in dss? You can use various stacking algorithms to improve the signal/noise. Also, there is the option to align the histogram after stacking, and increase saturation to much improve colour. The ST80 is a good little scope but it is an achromat with strong coma. Coma can be improved using the Startools lens function. Startools is free to download but doesn't let you save until you get a paid version (about Australian $50, I think) . Startools has lots of image processing functions. It's a good idea to take flats too. Also, you should think in terms of >20 calibration frames.

Louise

Edit:

Here's a quick and dirty reprocess of your .jpg in Paint.net:

attachicon.gifM31_pn.jpg

Oh my God !! That one was really good !!!!

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Oh my God !! That one was really good !!!!

Just to add - the image needs cropping as you can see borders from the registration process. Try taking shorter exposures but more of them. There are ways of processing to keep the core from burning out. I can't put my finger on one now but there are tutorials around with M31 as an example.

All the best!

Louise

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Hi Pankaj

That M31 looks like it has a lot of promise! You're right about dark skies - something most of us can only dream about! I'm sure you're image could be much improved with better processing. Not sure if you stacked in dss? You can use various stacking algorithms to improve the signal/noise. Also, there is the option to align the histogram after stacking, and increase saturation to much improve colour. The ST80 is a good little scope but it is an achromat with strong coma. Coma can be improved using the Startools lens function. Startools is free to download but doesn't let you save until you get a paid version (about Australian $50, I think) . Startools has lots of image processing functions. It's a good idea to take flats too. Also, you should think in terms of >20 calibration frames.

Louise

Edit:

Here's a quick and dirty reprocess of your .jpg in Paint.net:

attachicon.gifM31_pn.jpg

Lovely. Should I send you the original files?

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INSPIRED BY ALL THE COMMENTS AND FEEDBACK ON HOW TO IMPROVE IN POST PROCESSING, I HAVE REDONE THE PROCESSING ON THE ORIGINAL DATA. CONVERTED THE FINAL FILE IN .JPEG AND POSTING HEREWITH FOR CRITICAL COMMENTS PLEASE.  I VALUE EACH AND EVERY WORD IN THE FEEDBACK, AS IT HELPS ME TO IMPROVE FURTHER. HENCE PLEASE OPEN THE FLOODGATES OF YOUR SUGGESTIONS.

post-38054-0-13206900-1452626829.jpg

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Hello and congratulations to your M31!

You didn`t mention it, so i suspect that this was shot without autoguiding right?

If you would have an autoguider one could dither between the subs and therefore get rid of the "large" background pattern that i think i see.

I also have a question: What flattener did you use?

best regards

Matthias

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Hello and congratulations to your M31!

You didn`t mention it, so i suspect that this was shot without autoguiding right?

If you would have an autoguider one could dither between the subs and therefore get rid of the "large" background pattern that i think i see.

I also have a question: What flattener did you use?

best regards

Matthias

Hi Matthias

You are right. I dont use an autoguider yet. Plan to take that this summer. By the way, I didnt understand what you meant by 'large backround pattern.' Request you to please elaborate as it'll help me improve.

Regarding your second query about field flattner - I dont have one, so I didnt use it in this photo. 

Regards

Pankaj

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INSPIRED BY ALL THE COMMENTS AND FEEDBACK ON HOW TO IMPROVE IN POST PROCESSING, I HAVE REDONE THE PROCESSING ON THE ORIGINAL DATA. CONVERTED THE FINAL FILE IN .JPEG AND POSTING HEREWITH FOR CRITICAL COMMENTS PLEASE.  I VALUE EACH AND EVERY WORD IN THE FEEDBACK, AS IT HELPS ME TO IMPROVE FURTHER. HENCE PLEASE OPEN THE FLOODGATES OF YOUR SUGGESTIONS.

Hi

You've clipped the black point i.e. made the background too dark - you probably increased the contrast too much? By making the background too dark you lose some fine detail.

I don't think you can get a field flattener for the ST80 as it only has a 1.25" focusser. But the Startools lens function might help.

Louise

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Great images Pankaj. Having clear skies like you have must be great. I noted some comments about guiding. I just bought a guiding system for my set up and I've moved from 30-45 second exposures to 180-300 second ones, my success rate has increased from 30% to 90%+ and I'm using dithering to reduce the background noise. I hope your success to date inspires you to take more images. Clear skies. Richard.

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Great images Pankaj. Having clear skies like you have must be great. I noted some comments about guiding. I just bought a guiding system for my set up and I've moved from 30-45 second exposures to 180-300 second ones, my success rate has increased from 30% to 90%+ and I'm using dithering to reduce the background noise. I hope your success to date inspires you to take more images. Clear skies. Richard.

Thanks for the kind words Richard. 

About clear sky - I had to travel 400 km into Indian Himalayas to get to this location. I stay in New Delhi where the sky is so washed out that apart from brightest stars like Betelgeuse or Sirius, nothing is visible. I always wonder, what kind of Earth, our generation is will be leaving for our children.

Guiding - can you please suggest what kind of gear should I opt for. Cant afford really expensive ones until I get good experience in handling and operating an inexpensive one.

Warm regards

Pankaj

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