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I
"discovered" this large, bright planetary nebula one night while sweeping
at 95x with an OIII filter in place. A round glow came into view
and as I swept, another, very similar, round glow appeared in the same
field. The first glow was the globular cluster NGC 6712 (the previous
object in this month's tour). The second was the highly underrated
planetary nebula IC 1295. The two objects made quite a pleasing and
unexpected sight!
IC 1295 is typically cataloged as much fainter than it appears (sometimes as faint as 15th magnitude). It also responds strongly to the OIII and UHC filters. With one of these filters in place this little-known planetary appears as bright, or brighter than, the nearby globular! I think this planetary is a real show stopper. Its relative obscurity is probably due to the oft-reported erroneous integrated magnitude combined with the need of a UHC or OIII filter for it to really strut its stuff. The image above doesn't really do the planetary justice because it is a very blue object, which didn't record well on this red second-generation DSS image. Unfortunately, the blue DSS images are not yet widely available. In my 18-inch f/4.5 Dob, IC 1295 appeared large (similar in size to the globular with the OIII in place) quite obvious, and round. A small hole could be seen at the center, making it an annulus, but with very unusual proportions. The outer edges of the nebula appeared well defined (sharp) and somewhat irregular. When I removed the OIII filter the nebula all but disappeared, becoming much fainter and looking very different. Without the filter it appeared as a much smaller (perhaps half as large) diffuse glow, brighter near the center. It looked rather like a very diffuse elliptical galaxy but with an irregular, soft edge. In smaller scopes this nebula should appear as a small round patch. If you do not see it, be sure to use enough magnification (> 120x). Keep in mind that it can be a challenge without a filter. With the filter in place it should be visible in 6-inch scopes, if not smaller. The field in an 6-inch f/8. North is down and east is to the right. The nebula is the small smudge near the center. |
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