M57 (NGC 6720), The Ring Nebula,
in Lyra
M57 is one of the most famous of the planetary nebulae, the illuminated gases thrown off by a degenerating star. To the observer's eye, the nebula has the appearance of a perfect silvery-gray smoke ring, but to an imaging device, it has wonderful color and distinct internal structure. At its distance of 4100 light years, M57 is a very small target and it requires a long focal length telescope and steady seeing to capture any detail. The 2815 mm focal length of the RC scope used here is more than adequate, but the seeing conditions were not ideal
| Date | 2002-06-30 |
| Optics |
RCOS 12.5 inch RC at f/9 with ST-10 XME/CFW-8a on an A-P 1200 GTO mount. Guided with ST-10 internal guide chip. |
| Exposure |
RGB: 5 x 5 minute each, unbinned frames, SBIG filters. |
| Processing |
Calibrated and combined in MaxIm 3.07. Colors combined to RGB (1:1:1.3) in MaxIm. RGB levels adjusted, and dust & scratches filter, mild unsharp mask, and mild blur applied in Photoshop 6. |