M15 - A Globular Cluster in Pegasus
From the author of Welcome to the Universe in 3D
20:50 EDT Sep 10, 2017
Starlight Express Trius-SX694 on 10" RC at f/9.
R = 5 min, G = 5 min, B = 5 min in
20-second unguided exposures.
Combined with images from 2016.
Log stretch, (mild) unsharp mask, color saturation boosted.
Click here for Hertzsprung-Russell diagram.
21:25 EDT Oct 5, 2016
ClearSky rated the "seeing" as "good". FWHM = 1.6 to 1.8 arcsec.
Starlight Express Trius-SX694 on 10" RC at f/9.
20-second unguided exposures.
R best 25, G best 27, B best 24-ish out of 30.
Log stretch, (mild) unsharp mask, color saturation boosted.
Click here for Hertzsprung-Russell diagram.
Click here for blinking RR-Lyrae stars.
23:17 EDT Sep 5, 2015
ClearSky rated the "seeing" as "excellent".
Starlight Express SXV-H9 on 10" RC at f/9.
20-second unguided exposures.
L=24(30), R=19(24), G=21(24), B=23(24) exposures.
Images combined with those from 2013.
Log stretch, (mild) unsharp mask, color saturation boosted.
Color
Monochrome
Best single frame
01:36 EDT Jul 17, 2013
ClearSky rated the "seeing" as "excellent". FWHM = 1.22 arcsec or better.
Best luminance frame had FWHM = 1.06 arcsecond.
Starlight Express SXV-H9 on 10" RC at f/9.
20-second unguided exposures.
L best 60 out of 90. R, G, B best 20-ish out of 30.
Log stretch, (mild) unsharp mask, color saturation boosted.
Click here for Hertzsprung-Russell diagram.
Combo Version
23:47 EDT Sep 15, 2007 and 18:34 EST Nov 25, 2006.
Starlight Express SXV-H9 on 10" RC at f/9.
L from Sep 15, 2007 (below) and
R, G, B images from Nov 25, 2006 (below).
Log, Gamma, Unsharp Mask.
23:47 EDT Sep 15, 2007.
Starlight Express SXV-H9 on 10" RC at f/9.
L = 33.0 min (guided 1-minute subexposures, best 33 out of 156).
R, G, B images from Nov 25, 2006 (below).
Log, Gamma, Unsharp Mask.
18:34 EST Nov 25, 2006.
Starlight Express SXV-H9 on 10" RC at f/9.
L = 10.0 min, R = 5.0 min, G = 5.0 min, B = 5.0 min
(guided 20-second, 1-minute, and 5-minute subexposures).
Log, Unsharp Mask.
20:38 EDT Sep 25, 2006.
Starlight Express SXV-H9 on 10" RC at f/9.
L = 23.3 min, R = 6.0 min, G = 6.0 min, B = 6.0 min
(unguided 20-second subexposures).
Log, Unsharp Mask.
23:10 EDT Sep 4, 2005.
Starlight Express SXV-H9 on 10" RC at f/9.
L = 19.7 min, R = 3.3 min, G = 4.3 min, B = 3.3 min
(mostly unguided 20-second subexposures).
Log, Unsharp Mask.