IC1805 – Heart Nebula
The Heart Nebula is located between Cassiopea and Perseus. It is a large area that required a 2-pane mosaic to cover. There is a star cluster at the center of the nebula, catalogued as Melotte 15, and a huge amount of dusty filaments.
This was my first pleasantly successful mosaic with the Atik Horizon2. The large field of view covered by the combination of the ED80T and the Horizon is ideal for this target, and many details are retained.
The 2-pane mosaic frames the top and bottom of the object. I captured 4.5 hours in Hydrogen-alpha for each pane, and half an hour of Red, Green and Blue. The thirty minutes of RGB were damaged by calibration problems, but the outcome is nice nonetheless. I also discovered that leaving 15 percent of overlap between panes was really not much. Cropping to remove alignment and integration artifacts did not leave much space for stitching!
I adjusted the tint to be a tad more orange when printing on aluminium. That made the overall sanguine color less aggressive, and also smoothed the dark transition at the bottom left. For various reasons related to support, transitions to dark areas are always a problem when printing, even on aluminium.
Capture was brillantly executed by KDE KStars/Ekos over a few nights in October 2020, while the target was setting at north-west. I processed calibration and mosaic using Pixinsight.