The Devil's Tower- RCW 85

An image in Ha RGB

 

Located between Hadar and Rigel Kentaurus, this nebula has recently become quite a favourite for astroimagers

 

Location : Bortle 6

 

Equipment

Sharpstar z4/Antlia 3 nm Ha filter/ Antlia Triband RGB filter/ZWO 533 Mm pro -for H-alpha /6/533 MC pro for RGB colour/ASIAIR/HEQ5/ASIAIR

 

Data

 

4 hours in RGB (5 minute subs)

 

8 hours in Ha (10 minute subs)

 

20 minutes in RGB ( 60 second subs) -for stars

 

 

Processing

 

stacked in AstroPixelProcessor, processed in PixInsight

 

Processing Notes

Ha and RGB separately

 

Stack

register Ha, RGB long and RGB short stacks

Dynamic Crop

GraXpert

Blur X -correction

Image Solver

SPCC

Starnet++

 

Nebula

BlurX

NoiseX

GHS

NoiseX

Dark Structure Enhance ( for Ha only)

Curves Transformation

 

Stars

 

SetiAstro star stretch script

 

HaRGB image constructed using Foraxx utility in PI :

 

Synthetic OIII constructed as follows:

 

RGB image split into r,g and b

 

OIII=( 0,55*G +0.55*B)- 0.1*R

on the assumption that some red leaks into Blue and Green, 10 % is just a guess

 

Starless image in Foraxx constructed using Paulyman's script in PI

 

Curves Transformation after applying a luminance mask

 

Stars and starless combined with Pixelmath

 

Minor tweaking including a final crop - in Photoshop CS6

 

See also Starless version in Ha

 

flic.kr/p/2qixzHK

 

Done