Author Topic: Halpha and SII false color composition of the Flaming Star  (Read 827 times)

Offline astroedo

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Hi all

During the Halloween week end I got some Narrow Band data on the Flaming Star Nebula.
Waiting for the OIII data I've tried a weird experiment: a false color composition of Ha and SII

Ha and SII emisson lines lays both in deep red so it is impossible to render color differences in a real way: the only option is a false color composition.

In this image Hydrogen emission has the usual pinkish color due to the Ha and Hbeta emission lines.

As said before the SII emission line lays in deep red, but on Earth the cristalline sulfur has yellow hues so my goal was to render the SII in yellow.

To accomplish My Goal I've used the PixelMath tool in PixInsigth.

The composition formula was:

R Channel: Ha
G Channel: SII
B Channel: 0.25*Ha - 0.75*SII
The B channel formula is very simple the 0.25*Ha acconts for the Hbeta emission giving to the Hydrogen emission the usual pinkish color, subtracting the SII emission shifts the color hue of the Sulfur rich zones toward yellow the 0.75 factor is an arbitrary value chosen to render the wanted color.

See also on my site

and Astrobin
« Last Edit: 2015 November 03 13:57:13 by astroedo »