Combination of 12 5-minute images with an H-alpha filter, 12, 5 minute images with an SII filter and 12, 5 minute images with an OIII filter.
SBIG ST8XE CCD. 100mm f/4 Nikon lens.
IC 1805 is an unusually shaped emission nebula in eastern Cassopia, situated about 5 degrees north of the "double Cluster" in Perseus. Its nickname, the "Heart Nebula", derives from its shape as it does look like a big red valentine in the sky. The open cluster at the centre of the heart is Mel 15, while the bright patch of nebulosity at the base of the heart (upper right) is IC 1795. To the left of the heart is the bright open cluster NGC 1027.
The above image was processed using the H-alpha images as the red channel. This is the preferred palette of the European Southern Observatory. The HST observers prefer to use the SII images as the red channel since the SII line is at a slightly longer wavelength than the H-alpha line. This results in a more green-dominated image as shown below.
