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So what might your workflow be for this image of Lagoon?

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#1 Ballyhoo

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Posted 23 June 2022 - 04:07 PM

I still think of myself as quite the newbie when it comes to NB. For example I just know how to map using channel combination and  I do not have a solid workflow for adding LRGB data.   I map the classic SHO, , Oiii to blu, HA to green and SII to red.   

 

Would love to know how you would approach this image, which I feel comes from rather good data.  23 x300 sec Sii, 28 X 300 HA, " " for O2.  I used my ES FPL53 115 [F5.5]  triplet with a .8 Televue reducer and I do have some tilt in the lower left that I am not losing sleep over yet.  I also found last night that I did not have quite enough counter weight on my rig but I would not sweat that I am sure the Mach 1 could handle a little bit of a telescope heavy rig.

 

My process so far is 

 

DC

DBE

LF

Channel combination

non-linear stretch.

SCNR to reduce green, invert, do again.

invert again

 

After this there are several different options and I would love to read how others would approach it. I have linked a SHO master file for those interested:

 

  https://1drv.ms/u/s!...Iyzgzw?e=gM2PNI

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  • lagoonJun22.jpg


#2 Ballyhoo

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Posted 23 June 2022 - 04:15 PM

When I apply SCNR it instantly improves the image, but at the cost of data?

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  • lagoonJun22_SNCR.jpg

Edited by Ballyhoo, 23 June 2022 - 04:15 PM.


#3 Dren

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Posted 23 June 2022 - 04:31 PM

I usually like to do a little Hue adjustment before SCNR.  Sometimes I reduce the value of SCNR to leave a little green in the image.  Have you seen this tutorial?  I've linked to the color palette changes, but the whole tutorial is pretty informative.  


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#4 klaussius

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Posted 23 June 2022 - 04:36 PM

Instead of SCNR before inverting, I do "white balance" on SHO data. That almost always involves boosting OIII and SII considerably.

 

So, it would go:

 

  • DC
  • DBE
  • WB (linear stretch on SII and OIII to get pleasing colors)
  • Buld synthetic L = a*S + H + b*O for some value of a,b which I tune based on preference
  • WB matrix (apply a color matrix to turn green into a warmer color if I wish, depends on the image really whether I do)
    Commonly:
    • R = 0.75 * S + 0.35 * H
    • G = 0.65 * H + 0.35 * O
    • B = O
  • Invert
  • SCNR
  • Invert
  • Apply synthetic L

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#5 RogerM

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Posted 23 June 2022 - 05:01 PM

When I apply SCNR it instantly improves the image, but at the cost of data?

There was a conversation about using LinearFit during processing, I bookmarked Jon Rista' post for when I reconfigure back to NB.


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