This have been one of the worst winters for astrophotographing up here 65N. Somehow I managed to shoot six hours of H-alpha light for this target under a bad transparency, seeing was kind of good though.
Generally I'll like to shoot two or three times more exposures per target but if I'll do so, I might get only four new images per year... For the same reasons I have used my older, wide field, images as a source of color data. Naturally it's better to shoot all the color channel at same focal length but ones again, weather up here is too volatile for that.
OK, enough whining here. I proudly present the new image of IC 1805 from 5. January,
Black Lace, a detail of IC 1805, the Heart nebula
A closeup of IC 1805 in mapped colors. Edges of the triangle shape, at middle right, looks like a black lace.
A mosaic with Melotte 15
Since this new image of mine was overlapping with the Melotte 15 image, I made a two frame mosaic out of them.
A mapped color mosaic image shows the Melotte 15 at upper right corner.
Black Lace in natural colors
Natural color composition from the emission of ionized elements.
R=80%Hydrogen+20%Sulfur, G=100%Oxygen and B=85%Oxygen+15% Hydrogen to compensate otherwise missing H-beta emission. This composition is very close to a visual spectrum.
Orientation in the Heart Nebula
The area of interest is marked with a white rectangle.
INFO
The "Heart Nebula", IC1805 locates about 7500 light years away in constellation Cassiopeia. This is an emission nebula showing glow of ionized elements in a gas cloud and some darker dust lanes.
In a very center of the nebula, lays Melotte 15, it contains few very bright stars, nearly 50 times mass of our Sun, and many dim ones. The solar wind, a radiation pressure, from massive stars makes the gas twist to a various shapes.
Technical details
Processing work flow:
Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack2.
Levels, curves and color combine in PS CS3.
Optics, Meade LX200 GPS 12" @ f5
Camera, QHY9
Guiding, SXV-AO, an active optics unit, and Lodestar guide camera 8Hz
Image Scale, ~0,8 arc-seconds/pixel
18 x 1200s exposures for the H-alpha, emission of ionized Hydrogen = 6h
Narrowband cahnnels for ionized Oxygen and Sulfur are taken from an older wide field images.
A single unprocessed 1200 second frame of H-a emission
single 20 min. frame, just calibrated and stretched. Imaged with the QHY9 camera, Baader 7nm H-alpha filter and Meade LX200 12" telescope.
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