Imaged 11/18/2023 from patio in light polluted skies south of Boston. Celestron 8, Starizona Night Owl 0.4X focal reducer corrector, ASI294MC Pro, Orion Mini Autoguider. Averaged from 120 8s subframes. Processing: Stretched and reduced gradient processing using GraXpert A.I. method. White balancing and vibrancy in Paintshop Pro 2021.
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| M42 (Orion Nebula) |
In the previous post five interpolation methods, two AI, RBF, Splines and Kriging were compared for their effectiveness in eliminating background gradients. NGC7293 (Helix Nebula) was the target. The differences were subtle; however, to my eye, Kriging performed the best overall.
In this post only the latest AI (1.01), RBF, Splines and Kriging are compared by processing M8 (Lagoon Nebula), NGC281(Pacman Nebula) and M42(Orion Nebula). In the previous post stretching was done in Paintshop Pro 2021 (PSP21) before applying GraXpert. Herein GraXpert stretching was performed along with gradient processing. Also, for RBF, Splines and Kriging the same set of sampling points were used. For each set of four images the same white balance and vibrancy cosmetic tweaks were applied in PSP21.
The differences among the M8 images are very subtle; almost inconsequential. Kriging does appear to pull out a bit more nebulosity than the other methods. The differences are even more subtle among the NGC7293 images. The biggest differences among the methods are visible with M42.
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| M8 (A.I.) |
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| M8 (Kriging) |
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| M8 (RBF) |
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| M8 (Splines) |
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| NGC7293 (Splines) |
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| NGC7293 (RBF) |
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| NGC7293 (Kriging) |
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| NGC7293 (A.I.) |
I recently upgraded to GraXpert from v.1.06 (Dione) to v.2.02 which has added an AI interpolation method. The other three methods are Kriging, RBF and Splines. By coincidence I had recently imaged NGC7293 which rides only 25 degrees above my light polluted southern horizon. The result is an intense gradient including an imbedded "donut" that is not removed by darks and flats (calibration). All five GraXpert methods were applied. Of the five, to my eye, Kriging performed the best in reducing the gradient and reducing (but not eliminating) the donut residue. The five images just after applying GraXpert and Paintshop Pro histogram stretch appear below.
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| AI 1.01 |
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| AI 1.00 |
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| Kriging |
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| RBF |
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| Splines |
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| IC5146 |
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| Messier 13 |
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| NGC6882 |
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| NGC7023 |
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| Sharpless 136 |
I never tire of imaging these summer favorites. Setup: Celestron 8/AVX mount, Starizona Night Owl F/4 focal reducer, ASI294MC Pro cooled camera, Orion Auto Guider.
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| Messier 3 |
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| Messier 4 |
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| Messier 5 |
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| Messier 9 |
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| Messier 10 |
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| Messier 12 |
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| Messier 13 |
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| Messier 14 |
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| Messier 22 |
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| Messier 28 |
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| Messier 92 |
It was luck that I happened to image M101 on May 18 amidst "galaxy season". and just a day before the announcement of supernova SN2023ixf discovered by Japanese amateur astronomer Koichi Itagaki. I only became aware of the supernova a few days later and thanks to a spring high pressure system managed to image M101 on the 26th despite a high in the sky waxing near first quarter waxing moon. The two images appear below. The supernova appears in the top spiral arm above and left of the galactic center.
Equipment used: Celestron 8 on AVX mount, Starizona Night Owl 0.4x Focal Reducer, ZWO ASI294MC Pro camera, Orion Magnificent Mini autoguider. The 5/18 image was averaged from 60 x 30s subframes while the 5/26 image was averaged from 30 x 60s subframes.
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| M101(5-18-2023) |
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| M101 + SN2023ixf (5-26-2023) |
This backdated post is for DSO images acquired up to during May 2023 except for M101 and its supernova. M101 was imaged by luck on May 18th, the day the supernova was reported and later on May 26th. A post devoted to those images was published May 27. Setup: Celestron 8/AVX mount, Starizona Night Owl F/4 focal reducer, ZWO ASI294MC Pro cooled camera, Orion Magnificent Mini Auto-guider. Autostakkert!3 and Paintshop Pro employed for image processing.
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| Messier 51 (Whirlpool Galaxy) |
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| Messier 61 |
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| Messier 104 (Sombrero Galaxy) |
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| Messier 94 |
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| Messier 63 |
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| Messier 64 |
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| Messier 49 |
This post is backdated to April 10, 2023 the day on which all my April imaging occurred. Setup: Celestron 8 SCT, Starizona Night Owl f/4.0 focal reducer, ZWO ASI294MC Pro cooled camera, Orion Magnificent Mini Auto-guider. Processing: Autostakkert!3, Paintshop Pro 2021.
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| IC447 |
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| NGC2175 |
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| Sharpless 274 |
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| Messier 34 |
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| Messier 39 |
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| NGC 129 |
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| NGC 225 |
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| NGC 457 (Owl Cluster) |
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| NGC 663 |
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| NGC 774 |
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| NGC 7039 |
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| NGC 7082 |
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| NGC 7243 |
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| NGC 7789 Caroline's Rose |
