|
Instrument |
12.5" RCOS @
~f/9 (2880 mm fl) at 0.64 arcsec/pixel. Shown at 2.56 and 1.20 arcsec/pixel. |
|
Mount |
Paramount ME |
|
Camera |
SBIG STL-11000 w/
FW8 filter wheel, AstroDon Gen-2 Filters |
|
Acquisition Data |
9/23/2014
to 9/29/2014 Chino Valley, AZ... with CCD Commander & CCDSoft,
AOL guided. |
|
Exposure |
|
RGB |
495 min. (11 x 15 min.
each) Bin 1x1 |
eXcalibrator RGB
ratios are 1.00, 0.86 & 0.92 |
|
Software & Processing Notes |
-
CCDSoft, CCDStack,
PixInsight & Photoshop CS6.
-
eXcalibrator
v4.30 for (g:r) color balancing, using 260 stars from the
SDSS-DR9 database.
-
CCDBand-Aid to repair
KAI-11000M vertical bars.
-
CCDStack to
calibrate and register the sub
exposures and create the RGB image.
-
PixInsight
processing includes gradient repair and non-linear stretching.
-
PhotoShop for
the final touch up.
|
|
Comment |
North is to the top.
NGC 6940 was
discovered by William Herschel in 1784. The sparse open cluster is
in the constellation Vulpecula, at a distance of about 2,500
light-years. The intermediate aged, about 700 million years, cluster
consists of at least 170 stars. |
