|
5
|
Click the image for a ~ 57% size
wider view. (1800 x
1200 - 1.02 MB)
|
Instrument |
12.5" RCOS @
~ f/9 (2880 mm fl) at 0.64 arcsec/pixel. Shown at 0.85 and
1.11 arcsec/pixel. |
|
Mount |
Paramount ME |
|
Camera |
SBIG STL-11000 w/
FW8 filter wheel & AstroDon Gen-2 LRGB filters. |
|
Acquisition Data |
4/18/2017 to
4/25/2017 Chino Valley, AZ. with CCD Commander & CCDSoft. AOL
guided |
|
Exposure |
|
Lum |
510 min (17 x
30 min. each) Bin 1x1 |
|
RGB |
405 min ( 9 x
15 min. each) Bin 2x2 |
eXcalibrator RGB ratios are 1.00,
1.18 & 1.33 |
|
Software & Processing Notes
|
-
CCDSoft, CCDStack,
PixInsight, Photoshop CS6.
-
eXcalibrator
v5.0 for (g:r) color balancing, using
37 stars from the SDSS-DR9 database.
-
CCDBand-Aid to repair
KAI-11000M vertical bars.
-
CCDStack to
calibrate all sub exposures, data reject and combine the color
data and create the RGB
image.
-
PixInsight to
register, normalize, data reject, combine the luminance sub
exposures, gradient removal, non-linear stretching with
HistogramTransformation and to create the LRGB image. Selective
use of HDRMultiscaleTransform, with various layer counts, was
used to enhance the detail of the galaxies.
-
PhotoShop for the final touch-up.
|
|
Comment
|
Shown rotated 75°
clockwise.
Hickson 61, A.K.A The
Box, is compact galaxy group in the constellation Coma Berenices.
The topmost galaxy is NGC 4175. Continuing clockwise, the galaxies
are NGC 4173, NGC 4170 and NGC 4174.
|
|
