|
Instrument |
12.5" RCOS @
~ f/9 (2880 mm fl) at 0.64 arcsec/pixel. Shown at 0.85 and 2.0 arcsec/pixel. |
|
Mount |
Paramount ME |
|
Camera |
SBIG STL-11000 w/
FW8 filter wheel & AstroDon Gen-2 RGB filters. |
|
Acquisition Data |
10/2/2017 to
10/6/2017 Chino Valley, AZ. with CCD Commander & TheSkyX. AOL
guided |
|
Exposure |
|
RGB |
300 min (20 x
5 min. each) Bin 1x1 |
|
|
Software & Processing Notes
|
-
CCDStack,
PixInsight, Photoshop CS6.
-
eXcalibrator
v6.2 for (g:r),(b:r)
color balancing, using 1,685 stars from the Pan-STARRS database.
-
CCDBand-Aid to repair
KAI-11000M vertical bars.
-
CCDStack to
calibrate the sub exposures.
-
PixInsight
processing includes
CosmeticCorrection,
data rejection, mean combine the sub-exposures, create the RGB
image,
gradient removal and non-linear stretching with HistogramTransformation.
-
PhotoShop for additional background neutralization
|
|
Comment
|
The cluster is shown
rotated 160° counter clockwise.
NGC 6709 is an open
cluster in the constellation Aquila at a distance of about 3,500
light-years. The cluster has about 60 stars and is about 315 million
years old. The many slightly blue stars are are evidence of the
cluster's relatively young age. By comparison, our cooler more
yellow Sun is about 4.5 billion years old. |
