Between grandkids coming for Easter I finally got my version of the Monkey Face Nebula processed. I didn't realize that the far east end of it, mostly out of my frame, was a reflection nebula as well as emission. I'd have slid it over to get more of it. I was more interested in giving some contrast edge to the face at the time.

The O6.5 star that causes this nebula to glow really excites the OIII emission as well. While this is a pure LRGB image with no narrow band data the core of the nebula looks rather bluish from the OIII emission near the illuminating star. H-beta contributes a bit to it as well. Looking at a narrow band image of this nebula I see it has unusually strong sulfur emission around the edges. This is red like H-alpha and adds to the red color around the edges turning it more red than the usual pink of H-alpha and H-beta alone.

All in all it makes for a rather colorful emission nebula.

Note that south is at the top. It didn't look right standing on its head when I used my normal north up orientation.

The bright knot at the very bottom, a bit left of center is NGC 2174.

Also sharp eyed viewers may note two asteroids in the image. Near the top center is (40411) 1999 RM3 at an estimated 19.4 magnitude. Toward the bottom and a bit more to the right is (23124) 2000 AW82 at an estimated magnitude of 18.5. While the Minor Planet Center estimates the latter to be almost a magnitude brighter, it is in a denser part of the nebula and harder to find. Though I sometimes wonder about the Minor Planet Center's magnitude estimates. Due to them being in the nebula I was unable to get a good magnitude estimate on either with my software.

14" LX200R, L=4x10' binned 2x2, RGB=2x10' binned 3x3, STL-11000XM, Paramount ME

Full size image is at:
http://www.spacebanter.com/attachmen...tid=1796&stc=1

Yeah, I know its "Monkey Head" but the granddaughter (10) was looking at it as I processed it and said "Look at that cute monkey face". I can't get it out of my head now.

Rick

Attached Images

NGC2174LUM4X10RGB2X10X3R1-67.jpg (140.5 KB, 32 views)

Nice close-up of the Monkey's head. I'll add RGB data to my widefield image in the next couple weeks, if weather cooperates, and finish the exposure data collection for the final (LHa)(RHa)GB of this nice emissions neb/open cluster.

By the way, NGC2175, originally listed as GC1366, is the open cluster discovered by Hodierna, and later, Bruhns. Some of the DSS listings place 2175 at the center of the HII region, but most compilations, and planetarium programs, place it at the corner of the emission region, at the back of the Monkey's head, near it's neck. Similarly, some compilations call the single small bright HII region 2174, others note that 2174 is the larger HII region which encompasses 2175.

Robert
www.galacticphotography.com

The IC/NGC project rejects that and says it is the whole nebula. That's what I went with.

"NGC 2175 is a very large roughly circular emission nebula which also includes NGC 2174 and IC 2159 (both of which see), and a star cluster which has inherited the NGC number, though there is no mention of it in the discovery notes. The nebula is centered on SAO 078049, though the brightest knot (which Bigourdan took for N2175; hence, the ``corrected'' RA in the IC2 Notes) is about three arcmin to the west-northwest. Auwers's note makes it clear that NGC 2175 is much more than just the knot: he gives dimensions of 25 arcmin by 8 arcmin, and specifically adopts the position of Lalande 11668 = SAO 078049 as that for the object. I have followed his lead. - Dr. Harold G. Corwin, Jr."

http://www.ngcic.org/pubdb.htm

Rick

Very Beautiful indeed Rick, Simply Awesome lots of variety of cloud/dust structures and the stars looks great also the asteroids. Rick what is your fov for this photo do you use a Reducer/Flatner on this photos or is it the camera with its large chip that makes it fit in this frame?. Clear Skies

Great work capturing the complexity of this one. Its hard to tell where emission leaves off and reflection takes over as there are elements of both throughout the central cloud. I love the small pink emission 'bubble' with the dark band at the centre. Thanks again Rick.

Kind regards
Matt

FOV is at 1.003" per pixel and is 2004x1336 (full image link) so you can do the math, a bit over a half degree wide. To get it down to the bandwidth limit for the site I went to 1.5" per pixel and more compression, same field however.

No reducer or flattener. It is useless to me. The chip covers the full FOV of the scope so all I'd do is reduce the resolution. The corners would be heavily vignetted as the scope's baffles are 1.75" in diameter, virtually the same as the chip diagonal size. I have about 20% vignetting now as that baffle is a good foot in front of the camera. By binning 2x2, the most my seeing normally allows, I'm, in effect, running f/5. So in theory I could use a reducer then go to 1x1 binning and gain a tad of resolution at f/6.3. I'd need twice the exposure time and my weather is rarely up to that. Neither is my average seeing. The only full image at 1x1 binning I ever tried pushed things too far.
http://www.prairieastronomyclub.org/...0RGB2X10C3.jpg

My setup can't even take a reducer. I have 4 ports I can send light to. One is the off axis guider so always has light. Another port gets this camera, straight through, a third port has a mirror I can insert that directs the light to my ST-7 I use for photometric work along with its filters. The 4th port, also mirror selected is the eyepiece port. That allows me to view visually without dismounting the camera and the need for new flats when I put it back on again. The way these ports work there's no place for a compressor even if I wanted one, which I don't. Between this and the scope is a 3" Crayford focuser with temp compensated RoboFocus motor driving it. The standard Meade 2" focuser heavily vignetted and was way too weak to carry the load without sagging. Also this scope needs temperature compensation as its focus can change drastically during an exposure. In fact most of the distortion you see at the edges of my images are due to image scale changing with temperature. Sometimes I live with the elongated edge stars, other times, when it is too much for me, I resize all the images to the same scale. That can be up to 10 or even more pixels. One night it was about 60 but that was an extreme example. Temp dropped over 20 C in 2 hours!

The field isn't perfectly flat but it is better than a standard 14" SCT covering the same field with a telecompressor/flattener at this resolution.

For deep sky astrophotography the 14" LX200R is certainly an improvement over the standard scope. I just wish it had been made with a carbon fiber tube. That expense would be well worth it. Since they have announced this model won't be made under the post law suit name I'm sticking with the only name it will have.

Rick

Most of that center blue I believe to be due to the heavy OIII emission this nebula has. Closer to the exciting star the more OIII is favored over HII. Looking at some narrowband images that take this with OIII as blue, HII as green and SII as red you find the core is again very blue. The OIII blows out the HII there. Sulfur dominates the edges, another weird thing about his nebula. Here's a link to Richard Crisp's image with the above color assignment.
http://www.narrowbandimaging.com/ngc...2hao3_page.htm

Rick

Thanks for the link and yes I see what you mean by the OIII. I think I may add one of these filters to my wish list.

Kind regards
Matt

Thanks Rick for the info.