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View Full Version : vdB 158, LBN 534 and PK 110-12.1



RickJ
2011-Dec-20, 06:56 AM
The large nebula extending well beyond my image is the reflection nebula LBN 111.05-12.46 aka DG 191 aka LBN 534. It is located in Cassiopeia. The B8V star HD 222142 illuminates the blue reflection nebula vdB 158. Though many consider vdB158 as the same as the far larger cloud LBN 111.05-12.46 this is incorrect from what I found. Are they two separate objects or is HD 222142 in the larger cloud but only illuminating the smaller nebula? I found only one estimate, in the Italian Wikipedia, of the distance to vdB158 saying it is about 440 parsecs away (1435 light-years). I don't know if this is meant to apply to the larger cloud or just the blue nebula around HD 222142.

Also in the image is the planetary nebula PK110-12.1 down in the lower left corner of my frame. One paper puts its distance as 13,620 light-years. I expect there are too many significant digits to that distance estimate. If correct then the nebula has a diameter of about 2.25 light-years.
http://articles.adsabs.harvard.edu//full/1992A%26AS...94..399C/0000399.000.html

There are quite a few galaxies in the image if you hunt for them. All NED lists are from the 2MASS IR survey. NED shows no redshift nor magnitude data for any of them. The majority aren't in NED being anonymous as far as I can tell.

Image has been reduced to 1.5" per pixel to meet bandwidth limits. I just couldn't compress any more without ruining it so had to reduce it.

14" LX200R @ f/10, L=7x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Right click the image and select view image to see full size. Much is lost otherwise.

Rick

Graham
2011-Dec-20, 11:31 PM
Very nice and looks very nicely processed. Love the planetary!

Maybe could be a bit brighter across the image but that is personal taste also.

Great image.

RickJ
2011-Dec-21, 08:51 AM
I don't like brightening any more than here as it compresses dynamic range and some nuances are lost. A correctly adjusted monitor will show the bottom and top levels of the attached calibration strip and thus show all in my image.

Rick

Graham
2011-Dec-22, 07:48 AM
That is why I said it is personal taste. You could brighten without compressing. Still, it is a fine image.:)

RickJ
2011-Dec-22, 08:20 PM
A monitor only has a fixed range. Brightening the image must compress the upper range since it can't expand further. Unfortunately monitor settings and capabilities vary extensively so no one setting works for all. I set for monitors that see all ranges in the above chart as equally different. The viewer can then brighten or dim either end to suit their monitor.

Rick