NGC 6791 - Ancient Open Cluster in Lyra This is a magnitude 9.5 open cluster in Lyra that resembles more a globular than it does a normal open cluster. Consisting mainly of ancient yellow stars in the cluster itself, you see a sprinkling of younger blue stars in the foreground. This cluster is less than 1 degree SEE of Theta Lyra. Taken: - 6/16/2006, 6/21/2006 Conditions: - Transparency very poor, seeing about 5 (very poor night...but the first opportunity to image in weeks due to rain, so I coudnt resist.) Equipment: - TOA-150 - SBIG ST-2000XM, self-guided - ST CFW-10, Astrodon LRGB filters - FLI PDF Exposures: (170 minutes so far) - L = 9x2mins + 8x3mins (42mins) - R = 10x2mins + 8x3mins (44mins) - G = 9x2mins + 8x3mins (42mins) - B = 9x2mins + 8x3mins (42mins) Processing: CCDStack: - initial sub registration - RGB combine, used to generate synthetic luminance (Ls) - Ls mean combined with the natural L - Deconvolution (Positive Constraint, 25 runs) - DDP - LsLRGB combine PSCS2: - gradient control (see my gradient control tip in the tips and tricks section) - noise control (NeatImage) - slightly increased hue and saturation (Interestingly enough, I did NO increased saturation on the bright orange star in the upper left!) - curves to bring up the mid-tones - slight sharpening via Smart Sharpen in PSCS