Sunday Night Imaging Run

October 10, 2023

I spent most of the night capturing OIII (Oxygen 3) and SII (Sulfur 2) data in the IC1396 region in Cepheus, enough to combine with last week's Ha (Hydrogen-alpha) data to create a SHO color image, mapping sulfur to red, hydrogen to green, and oxygen to blue in RGB. I've balanced the RGB intensity, but left green for Ha a bit higher. Hydrogen is the most abundant element in the universe—by a very wide margin, and without balancing the Ha, OIII, SII channel values, most nebulae would be overwhelmingly green. That said, I do like to keep more hydrogen green in my images, making them a bit truer to the emission values of most deep sky objects.

I spent the last three hours of the night capturing Ha data of NGC 1499, the California Nebula, about a thousand lightyears away in the constellation Perseus. 

astrophotography NGC 1499