In the end, I had gotten rid of most of the artifacts and ended up with an image that looked "better", but I had to admit that Gamma Cas did not look very natural. Arrrrrgh!Īs you can see in the processing details below - I also had to jump through some hoops to deal with the problems around the bright star Gamma Cas. I was going to have to do a deep crop to eliminate the areas that were not common to all subframes. The result of this is that my Master images have some areas of sharp nonuniformity. I must never have turned it back on.Ĭlassic operator error! 0bviously, I need to get a smarter operator! I did have this setup when I shot the first night's subs, but I must have turned this off at the end of the night when I was setting to shoot flats and flat dark calibration frames ( I don’t need centering or rotation when shooting darks or flats). Or at least it does if I have the sequence set up to actually do rotation. It automatically moves the scope and rotates the camera to get to the specified position. I discovered that the rotation of the camera ended up being different between night 1 and the other nights! How did this happen? When Sequence Generator Pro "centers" an image before starting exposures, it uses plate solving to verify both the position in the sky that the scope is pointed to and the rotation of the camera. So I blew the objective off and brushed it and this cleaned it up nicely - but a big chunk of my data would still have the problem. After the first night of capture, I noticed some issues with star bloat and halos and artifacts on bright stars - so I checked the telescope objective and saw that it had a lot of dust that had accumulated there over the summer. I knew this was going to be tough to deal with. I also saw that I had some bloated stars and a horrible case of microlens reflections on the bright star Gamma Cassiopeia. It does, however, take a bit more time and fussing around to do this. This then allows the high and low rejection logic to do a better job and allows portions of a subframe that have viable data to make their contribution to the integrated whole. This “flattens” out the gradients and puts the full set of frames on a more even footing. This allows variable gradients on each subframe to be normalized to a selected reference image. In the past, I would have deleted frames thus impacted by thin clouds, but it is now my practice use to leave them in and use Pixinsight's NormalizedScaleGradient tool to manage the integration of the image. When I reviewed the images using Blink, I saw a lot of thin clouds passing over the target region for portions of 3rd and last evening. I could tell right off that the image processing for this project would be very demanding. LRGB data was collected with 90-second subs, while 300-second Ha subs were also collected. ![]() This shot was taken with the Willian Optics 132mm Platform using the ASI1600mm-pro camera. This is the fourth target to be processed from data that was collected over the nights of November 5th through the 8th. Located to the left in the image above, is also IC 59 - another region of gas that is also excited by the same star. Areas of blue can also be seen, which is due to light reflected from the gas dust in the nebula. ![]() and baths it in ultraviolet light, which causes the hydrogen gas to glow in the red part of the spectrum. Added to this is the fact that it is only 3 or light-years away from the nebula. It has a radius that is 14 times larger than our own Sun, while also being 55,000 times more luminous and 19 times more massive. This Blue-White Giant star forms the middle star in the "W" form made by the constellation. The gas and dust in this region are bombarded with radiation from the bright star Gamma Cassiopeia. ![]() This region is both an emission nebula and a reflection nebula. IC 63, also known as "The Ghost of Cassiopeia", is an area of molecular hydrogen clouds and dust located 550 light-years away in the constellation, appropriately enough, of Cassiopeia.
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