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Globular M14

Started by jthommes, 07/06/2008 09:10PM
Posted 07/06/2008 09:10PM Opening Post
Here is an image of one of the 5 Messier Globulars in Ophiuchus - M14. I am a bit unsure of the colors. Seems that the Green and Blue exposures saturated at 36,000 ADU whereas Red was my more normal 56,000 ADU that I usually see with my Artemis285. (The Artemis285 does not top out at 65535 like you would expect of 16 bits) Not sure what the deal was on the Green and Blue. I scaled the Green and Blue up accordingly and produced what you see. (Though I notice many color images of M14 on the internet are very red - I assumed a color inaccuracy). Maybe it's me and the color is really very red.

Anyway, here is my version of M14:

http://jthommes.com/Astro/M14.htm

C8 (203 mm) at f/7.5
Artemis285 Camera - IR RGB filters
G11/Gemini
Guiding Megrez II at 1350 mm FL, DSI Pro, PHD Guiding

Here is an older image from 2004:

http://jthommes.com/MiscAstro/Archives/M14.htm

Jim Thommes

Mak-Newt 152 mm
C8
Megrez II APO
Zenithstar 66 mm APO
G11/Gemini
ST8300M
Artemis285 Camera
Canon 350D DSLR

http://jthommes.com/Astro/
Posted 07/06/2008 11:43PM #1
Posted 07/07/2008 01:09AM #2
Beautiful glob, Jim.

Tom

Starsearch Observatory
Lat 42N 47' 00" Long 112W 10' 47"
Elev 1752m
www.tvdavisastropics.com
Posted 07/09/2008 04:37AM #3
Mike, Tom,
Thanks for the comments.

Jim Thommes

Mak-Newt 152 mm
C8
Megrez II APO
Zenithstar 66 mm APO
G11/Gemini
ST8300M
Artemis285 Camera
Canon 350D DSLR

http://jthommes.com/Astro/
Posted 07/10/2008 01:45PM #4
Nice jump from that 2004 image. Yes, the colors look nice and balanced here, but I believe that it should be redder because of the older stars found in globulars. There shouldn't be any blue stars at all inside the "glob", but that might be hard to tell without an even bigger background field.

Charlie

Fort Lewis Observatory: (37.238, -108.052) ~2360m (7744 ft.) elevation.
Darkness - typically 6.5+
Scope - Meade 16" LX200; f6.3 focal reducer
Focus - JMI Smart focus
Camera - SBIG ST-10XE; (~.5"/pixel)
Guiding - AO-8 and/or Meade 5"/DSI/PHD
http://www.fortlewis.edu/observatory
Posted 07/12/2008 12:30AM #5
Hi Jim,

I have seen a lot of reddish versions of this one too.I'm not sure what is accurate but I like your processing and color on this very much,looks great!

Jason