The left image is a
straight RGB combine RGB 450 min (10 x 15 min each, bin 2x2)
The right image is an
LLRGB combine Lum 510 min (34 x 15
min, bin 1x1) RGB 450 min (10 x 15 min each, bin 2x2)
Taken w/ an
SBIG STL-11000 camera, using AstroDon Gen II Filters.
The speculation is that
because the STL-11000 camera's quantum efficiency is highest in the
blue, an image with excessive luminance data will be too blue. For this test, note that the luminance data is used twice in the
right image.
The R:G:B ratios were 1.00:0.88:1.18. This was determined by
eXcalibrator, with only six stars from the NOMAD1 database. The NOMAD
data sometimes produces a too-blue color balance. The color
balance is probably about right, as the star colors look correct.
However, color balance
is not in question for this test. We are looking for a difference
between RGB and LLRGB... they both look about the same. |