December: Test shots with new scopes/mounts
Dec 21: TMB 80/480 Arrives!
Dec 3: AP1200 Arrives!
Nov 30: TMB 152/1200 Arrives!
This is an update of my previous Horsehead Nebula image, with nearly 4hrs of Hα exposure added to the existing RGB data. The Hα really helps bring out many of the features in this busy field.
To create the HαRGB composite, I first added some Hα into the red channel of the original RGB data, which was then converted to Hue, Saturation, Luminance. Then I used a process similar to Photoshop's “Screen” blending mode to combine the luminance of the original RGB data with the (grayscale) Hα data. This Screen-blended Luminance, along with the Hue and Saturation of the Hα-enhanced RGB image, was then converted back to RGB. This method seemed to preserve details in the non-Hα-emitting regions, provide excellent detail in the Hα regions, and preserve the colors.
A higher-resolution image is also available. North is left.