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M 83, in Hydra
M83 is a large barred spiral galaxy in the largest constellation, Hydra. M83 was discovered from the southern hemisphere and at -29 degrees, 52 minutes is one of the southern-most objects visible from my latitude of 38 degrees North. In fact, while imaging M83, the telescope was barely skimming above the edge of the folded-down observatory wall. Because of its very low altitude, I didn't expect much of these frames and was pleasantly surprised that the final image turned out as well as it did. This is the first image I have done using the RoboFocus controller for focussing my A-P refractor. Based on the minimum star size I was able to achieve (1.8 pixels FWHM, MaxIm), this device does indeed improve fine-focussing.
M83 is part of the Centaurus galaxy group and lies approximately 22 million light years distant, according to Kepple & Sanner. Angular size is 15 x 13 minutes, so it fits well on the Kodak KAF401 CCD chip, which covers 31 x 18 minutes at 780 mm focal length. The well-defined arms show numerous reddish star-forming regions. Two extremely small, faint galaxies can be seen to the right of M83.
| Date | 2002-05-1 |
| Scope |
Astro-Physics 130 EDF at f6 on A-P 1200GTO mount; ST-4 guiding Meade 416XTE CCD camera with 616 color wheel controlled with MaxIm DL/CCD v3 |
| Exposures | L = 4 x 600 sec, unbinned; R, G, B = 4 x 300 sec, binned 2x2 |
| Processing |
Calibrated and RGB assembled in MaxIm, luminance enhanced with low pass DDP in MaxIm. Luminance and RGB combined in Photoshop and stretched and unsharp masked. Mild blur was applied to the RGB layer with SGBNR. |