Time Travel Research Center
© 2005 Cetin BAL - GSM:+90 05366063183 - Turkey / Denizli
The Western Veil (NGC 6960)
Ha:(HaR:G:B)- exposure time for Ha
was 60' as previously described (binned 1 x 1). Exposure times for R, G, B
were 18' each (binned 2 x 2).
Date for color data: June 20, 2004
Scope: Takahashi Sky 90 at f4.5 with field flattener/focal reducer, on the
G11 Losmandy Mount.
Autoguider: SBIG STV with e-finder.
Filter: Astronomik RGB type II filter set.
Exposures: 6 x 3' each color filter, binned
2 x 2.
Conditions: Temperature 50 degrees F; above
average transparency; below average seeing; breezy.
Post-processing: Color data: No dark, bias, or flat frames used. Each
color channel auto-aligned in MaximDL and sigma combined using RC Sigma
Reject plug in. The images were then normalized manually in ImagesPlus, RGB
combined, and DDP stretched to a yield a reasonable color read out.
Gradients were corrected in this RGB image by splitting into R, G, and B
channels, followed by use of the Background Compensation feature of
ImagesPlus (IP) on each channel. Gradient-corrected channels were then
recombined, and the RGB image was moved into Photoshop for merging with my
hydrogen alpha image as luminance. An HaR combine (50:50) was used for the
red channel. The technique of "Luminance Corrected LRGB" was used to
preserve luminance detail and color saturation. Notice the green-blue
tendrils representing areas of OIII emission in the above image.