Abell 13 PK 204-8.1

Here is a shot of an apparently little imaged planetary nebula in Orion. It is listed as magnitude 15.3 with a diameter of 174". This was taken with a C11 at f11.5, MI-250 and a ST-8XME at -40C with an AO8, CFW-10 through an Astrodon 6nm H-Alpha filter. This object has a very bright guide star available through this setup so much so that the AO8 used an exposure of only .6 sec for the guide star even through the H-Alpha filter. The previous post referenced storms and clouds and I share in the sentiment (located in MN). Almost everytime I tried to complete an imaging run, clouds and/or fog seemed to set in and ruined exposures. In the end (much to my surprise because I never kept count) I ended up with 44 subexposures of 10 min each over 4 or 5 nights.
I just recently purchased CCD Inspector/CCDStack and this image is the first time I used this software (previously only used CCDSoft). Also this is the first time I used CS2 to finalize the image. I am certainly a novice using this software combination. Fortunately it is winter and I have plenty of other images to get used to using that software combo.

Chris
Cedar, MN

Attached Image:

Cool. Where's the cheeseburger and shake? It definitely looks like an onion ring. Thanks for sharing this unique capture.

David

That's a new one for me, Chris.
There certainly aren't many images of this one out there.
I think that it is ever so slightly black-clipped. I was able to tease out some more faint stuff from the jpeg, so I'm sure that you can do better with the original data. CCDStack tends to set the black point a little high when using the defaults. Most people lower it before saving to tiff. It's easy enough to reset it after subsequent stretching in PhotoShop. God knows that you need every low end photon when imaging something as dim as this.
Well done on a difficult target.

dan

Excellent!!

Very interesting object Chris. Hopefully you plan on returning to Abell 13 once the weather is more accomodating. I would'nt mind seeing an RGB shot of this object.

Dean Jacobsen
http://astrophoto.net