The California Nebula

The California nebula is in the constellation of Perseus and is an emission nebula that is supposed to resemble the state of California. Its glowing red due to the large star at the top of the image named Menkhib, which is one of the hottest stars in the night sky at six times the temperature of the Sun. Its relatively close, between 1000 and 1500 light years away and only just fits in the frame.
I use an ASTRONOMIK CLS VISUAL Light pollution CLIP-FILTER in front of my Canon 40d astro-modded sensor which blocks light pollution like street lights but allows H-Alpha wave lengths which are red in colour such as ionised hydrogen.