Here is the first
of a series of images taken on November 3rd with the 12.5 inch
Newtonian at f/5, and a coma corrector. Shots were auto guided
with a Lumicon Newtonian Easy guider, and an ST4 for sets of
5 minutes each. I was greatly surprised how low the noise was
at ASA1600 used here, and multiple frames stacked made most of
it disappear. This is a mere 10 minutes of integration time -
Very short for an astronomical exposure.
Look carefully at this
image and you'll be able to spot the blue star clusters, and
an occasional pinkish HII region, usually represented with this
camera as magenta in cast.
Processing: Two RAW
frames were dark subtracted, and combined in PW Pro as negatives
using multiply. In Photoshop the image was reinverted, and levels
and brightness adjusted. A very small amount of SGBNR tamed the
small but residual grain to reduced acceptable levels.
Final Note: This camera
has a huge chip compared to my ST8i, and tons more Mega pixels.
For at least the brighter non Hydrogen Alpha objects, such as
bright galaxies, comets and star clusters, the concept of one
shot color is very attractive!
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