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M31 Andromeda - Updated

Started by ApophisAstros, Nov 02, 2017, 23:19:55

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ApophisAstros

I think this becoming one of my favourite targets.

Had another go from the begining without darkening.

Taken 29/10/2017 Worthing.
58 x 300 second subs
20 x flats
10 x darks
20 bias
Processed with the latest Photoshop64bit CC 2018 ,amazing piece of kit.
GradientXterminator and HLVG(Hasta La Vista Green)for green noise.Thanks Carole for heads up on those..
Roger

Kit

SkyWatcher 120ED Imaging System for Canon DSLR Cameras
Canon EOS 750D DSLR - Modded for Astro Imaging FOV 1.67 x 1.11 arc mins
Skywatcher EQ6-R PRO Synscan Skywatcher 9x50 Finderscope w/QHY5L-II MONO
Skywatcher 0.85x Focal Reducer/Corrector for Evostar-120ED
Incanus Ltd. Astro Photography Tool, 
Luc Coiffier Deep Sky Stacker 3.3.4
QHYCCD PoleMaster
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

MarkS

Wow - that's nearly 5 hours of data!

It's looking good but to improve it further you will definitely need to try it from a dark site.

Mark

ApophisAstros

Thanks Mark,
Yes i agree , but not bad given the moon and LP.
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Carole

Roger, try not to darken the sky too much, your black point is clipped (check the histogram), this is because you have darkened the sky too much.  That also has the result of losing some of the fainter details.

Carole

MarkS

Quote from: Carole
Roger, try not to darken the sky too much, your black point is clipped (check the histogram), this is because you have darkened the sky too much.  That also has the result of losing some of the fainter details.

That's good advice.  I never let my background go black.

Mark

Carole

That's much better Roger, I like it that way up too.

Carole

ApophisAstros

I think its because of the Meridian Flip as light no 45 (which up to this point included bright moon aswell) jumps to no 58 from which they are much better lights, so by the time i went out and realised i had to flip , i must have lost 13 lights,as i didnt change it in PS, i just some slightly different better lights so DSS must place it whichever way the most lights are.
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

The Thing

Quote from: Apophis on Nov 05, 2017, 11:15:37
I think its because of the Meridian Flip as light no 45 (which up to this point included bright moon aswell) jumps to no 58 from which they are much better lights, so by the time i went out and realised i had to flip , i must have lost 13 lights,as i didnt change it in PS, i just some slightly different better lights so DSS must place it whichever way the most lights are.
Roger

Hi Roger
Nice Andromeda's, I tend to make the background too dark as well, makes the image leap out of the screen but technically not good as you lose detail in the dim bits.

Use the groups functionality in DSS for before and after flip images, put the subs that are the best along with your calibration frames in Main Group, pick the one thats the right way up/best and right click then 'set as reference frame'. If there are different calibration frames for other groups stick them in the appropriate group. Sky differences are much better dealt with using the Groups as are different nights (when you may have to have different flats and darks).

After the first run through in DSS I deselect the calibration frames then add the Master (either TIF or FITS depending what you specified for intermediate files) ones DSS has created to the file list. Save reprocessing them. Also you can select an area on your reference frame and just process that while you tweak settings. Much much faster. Don't forget to save the file list!

HTH

Duncan


ApophisAstros

Thanks everyone, good advise from all as usual.
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.