IC 1805 & Melotte 15, Bi-Color (Sept. & Oct. 2013)

Full resolution image here.

This is the brightest part of IC1805 in eastern Cassiopeia.  The star cluster to the right is Melotte 15.  What is stunning about this area is how the ionization fronts twist and turn next to the star cluster.

This is a bi-color image, but Ha[+NII] dominates the scene.  The OIII is present nearly everywhere the Ha exists, but is dimmer.  I've included both monochrome frames below, Ha then OIII.

Telescope: Astro-Tech AT111EDT and William Optics AFR-IV (eff. at f/5.6)
Camera and Exposure: SXVF-H9 (Ha+NII:23x1200"; OIII:17x1200"), Alnitak Flat-man flats
Filter: Astronomik Ha+NII & OIII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX

M27 Bi-Color Narrowband (Sept. & Oct. 2013)

 

Full resolution image here.

M27 again.  Early in the summer I took some OIII of this object, but the frames had a guiding error.  They looked cool, though, so I've wanted to come back for more.  Also, I observed M27 from Bear Lake, Utah, this summer through my SV80ED.  It was stunning, a big cotton ball in the sky.  Too bad the imaging had to wait until late September, when M27 is only available for a few hours from my backyard.

This is a bi-color image, which in this case means that I concocted a synthetic green channel out of the OIII (80%) and Ha (20%) frames.  I opted to show OIII in blue rather than green (OIII is more green than blue) because red and blue look nicer to me than red and green.

Telescope: Astro-Tech AT111EDT and William Optics AFR-IV (eff. at f/5.6)
Camera and Exposure: SXVF-H9 (Ha+NII:13x1200"; OIII:9x1200"), Alnitak Flat-man flats
Filter: Astronomik Ha+NII & OIII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX

Dumbbell Nebula, M27, in OIII (Sept. 24, 2013)

Full resolution image here.

Finally, clear skies again.  I took a few images of M27 through an OIII filter in June and have wanted to go back to it.  This nebula is so dramatic in the light of ionized oxygen!  In fact, this nebula is quite a sight no matter how you look at it.  This summer while observing the excellent skies near Bear Lake, Utah, I glimpsed M27 in a low-power eyepiece through my SV80ED.  The nebula looked like a cotton ball, round and puffy, floating in the Milky Way!  M27 lies roughly 1,300 lights years distant in the constellation Vulpecula.

Telescope: Astro-Tech AT111EDT and William Optics AFR-IV (eff. at f/5.6)
Camera and Exposure: SXVF-H9 (OIII: 9x1200"), Alnitak Flat-man flats
Filter: Astronomik OIII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX

Crescent Nebula, NGC 6888, Bi-color (June 2012)

Full resolution image here.

Here is a bi-color combine of the Ha[+NII] and OIII data.  I had to tone down the Ha so that the OIII would show up.  The OIII is so dim from my backyard, and my camera so less sensitive to it, that I would have to take a lot more than 5 hours to brighten it up.  There are many great images of this object around the web.  Some of my favorites are Jim Wood and Emanuele Colognato's, here, and Ken Crawford's, here, taken with, respectively, 24" and 20" telescopes, and from darker skies.  The Crescent Nebula is about 5,000 light years away in the constellation Cygnus.

Telescope: Orion 6" f/5 Imaging Newtonian and Astro-Tech Coma Corrector (eff. at f/5.5)
Camera and Exposure: Ha (13x20'), OIII (15x20'), thru the SXVF-H9, Alnitak Flat-man flats
Filter: Astronomik 12nm Ha & OIII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX
Hat tip to Steve Cannistra for the bi-color processing method.

Crescent Nebula, NGC 6888, in OIII (June 24, 2012)

Full resolution image here.

Here is NGC 6888 in a wavelength dominated by glowing, ionized oxygen.  It is much fainter than the Ha, partly because my camera is less sensitive in this part of the spectrum.

Telescope: Orion 6" f/5 Imaging Newtonian and Astro-Tech Coma Corrector (eff. at f/5.5)
Camera and Exposure: 15x20' thru the SXVF-H9, Alnitak Flat-man flats
Filter: Astronomik 12nm OIII
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX

Abell 31 or PK219+31.1, OIII Added

With OIII added, Abell 31 looks something like this. The OIII is very faint. Even with 18x7' (126 minutes) of exposure through the Atik 16, stacked, the OIII was very dim. I stretched the data as much as I could. The Atik 16 is not nearly as sensitive to OIII as it is to Ha. Here is a version with less brightness:

Abell 33 or PK 238+34.1 (2-4-2011)

Abell 33 is a fine planetary nebula in the constellation Hydra. This is just 9x7' through an Astronomik 12nm OIII filter with the Atik 16 and 120mm achromat + WO 0.8x II ff/fr = astrograph.