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NGC 2070 Tarantula Nebula

  October 2017 - November 2017

One of the jewels of the southern hemisphere is the Large Magellanic Cloud.  I used to travel to Costa Rica to get a short glimpse of this.  On a longer trip to Australia in 2006 I spent an entire night with detailed charts moving from one object to the next using a portable 10" telescope and my eyes.

When I had the opportunity to start using the Chilescope this was one of the first objects I had in mind.  In October it was not in a favorable location until 3 AM, but that was fine with me.  I just queued the session and let the scope gather the data.

The full image is shown below.  Here is just the central part of the Tarantula at 66% size.

NGC 2070 in LRGB+H

Location of NGC 2070 Tarantula Nebula

Area map
zoom map

Above is a map in Alt Az as viewed from the Observatory. 

Annotated Image

The image is presented as North is left.

Annotated Image of NGC 2070 area

Zoomable Image

The full size image is about 3000x3250.  The following will allow the reader to zoom into the image to explore it more closely.

Processing Details

Here are counts of the raw frames that were used for the various filters.  Naturally more images were taken.  These represented the ones that made the cut. The data from the scopes was captured at -30C and was very clean.  Thus I could proceed with far fewer images than normal.

Lum 19x300
Red 20x300
Green 11x300
Blue 9x300
Halpha 9x300

All images were processed by Pixinsight. 

I collected 180 second Lum data as well.  I found it difficult to color correct the resulting HDR image so I ended up not using these.

I added Halpha into the image using the Vicent Perez method

HCorrect = Halpha - (R - Med(R)) * 0.5
Red = Red +(HCorrect - Med(HCorrect)) * 8

where 0.5 and 8 were chosen for the desired result.

The bright stars were all A or brighter so I was not able to do a proper color calibration.  I just assumed that R=B=G.  Adding Halpha significantly increased the red channel in the resulting image.  It also converted several dark nebula areas into a more interesting dark red color.

This image benefited dramatically from using deconvolution. In my home images deconvolution is not usually useful since I work in wide field.  The extra magnification of the 500mm scopes introduced enough atmospheric distortion that deconvolution did produce a result.

The image was otherwise processed in my typical way.

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Creative Commons License  (c) 2017 Robert J Hawley Some Rights Reserved.
Except as noted,all work on this site by Robert J. Hawley is copyrighted under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. This permits the non commercial use of the material on this site, either in whole or in part, in other works provided that I am credited for the work.