The Coal Sack Loop in H alpha- 12 panel mosaic

The “Coalsack Loop” is a 10 degree diameter ring of visible emission nebulosity centred on the Coal Sack dark cloud, which is seen in projection against the Loop’s centre. It was discovered only in 1998, and is very very faint and very rarely imaged

 

This image is a 12 panel mosaic- each panel consisting of an integration of 10 ten minute sub-exposures, or 100 minutes per panel

 

Total integration therefore represents 20 hours of data

 

For the full resolution image which allows panning and zooming in visit

 

www.gigapan.com/gigapans/230026#detail-sharegigapan.com/gigapans/230026#detail-share

 

Equipment

 

EQ6/ RedCat 51/Baader 7nm H alpha filter/QHY 183 MM

 

Software

 

NINA/ AstroPixel Processor/Photoshop CS6/ GraXpert/NoiseXterminator/Topaz AI/Starnet ++ v2/ Planning in Telescopius

 

 

Conditions

 

I started this project on May 6 but the weather has been so bad that i was able to only complete acquisition of 12 panels by mid July.

 

as a result data was collected under a wide range of conditions -moon, seeing and even light cloud, making processing a challenge

 

Processing notes

 

 

Stacked each pane separately as normal and then constructed a mosaic using the following settings:

 

Registration :

 

Mosaic

Scale stop : 15

Dynamic Distortion : ON

Normal Registration

 

Normalisation :

 

Advanced

 

Neutralise background : ON

 

Integration:

 

LNC 4 degrees , three iterations

MBB 20 %

 

used Graxpert for tackling gradients

 

both NoiseXpert and Topaz AI for noise reduction

 

starnet++ for star removal prior to processing the nebula

Done