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while adjusting the focus of the telescope.
During an imaging session, a folder is created on your
computer’s hard drive that holds all the light, dark, bias,
and fl at frames made for a given object. You designate
each type of frame using a pull-down menu before the
exposure is started. This makes processing the images
extremely easy. The Stack command begins by automatically
creating master fl at and dark frames from the appropriate
exposures in the folder. It then proceeds to calibrate
the light images with these masters.
The next step is to align and stack the individual calibrated
images by either letting the program automatically
select stars for aligning or by manually selecting a single
star that you identify in each image. When working with
about two dozen calibrated images, the processing time
needed to display a stacked image took about 2 minutes
on my late-model computer.
You then proceed to the Stretch step followed by
Smooth, Sharpen, Saturate, and Share. Each step has
user-settable sliders that control the amount of processing
done to the image, but there’s also the Auto mode for each
step, which produces really fi rst-class results with just a
single click of the mouse. I used this setting for processing
all the images accompanying this review. I can see
the Auto feature being a huge boon to people new to the
esoteric art of processing astronomical images.
The Share tab would be more aptly named “Save,”
because it simply lets you save the processed image in a
variety of fi le formats, including 16-bit FITS (a standard
for astronomical images). You can also save them as 16- or
8-bit TIFF fi les as well as JPEG format with three diff erent
levels of fi le compression.
The camera is supplied with standard ASCOM drivers for people who want to control the image-capture process
with other brands of imaging software. I successfully
tested it with Nebulosity (available from www.stark-labs.
com) and Images Plus (www.mlunsold.com). Regardless
of which astronomical program I used to capture
and process exposures in the past, I usually opened the
“fi nished” images in Adobe Photoshop for fi nal tweaking.
With AstroFX, however, this wasn’t necessary — the software
did an excellent job by itself. I’m impressed.
If Celestron was trying to create a high-quality, oneshot
color CCD camera with regulated cooling and easyto-use
software, they’ve certainly done it with Nightscape.
Astrophotographers who have used DSLRs or small-chip
cameras for deep-sky imaging and are looking to upgrade
to a high-megapixel, dedicated astronomical camera
should strongly consider Nightscape. And if you’re a
beginner when it comes to astronomical image processing,
AstroFX can be your step-by-step guide to rewarding,
high-resolution deep-sky images. ✦
The Stretch function renders deep-sky objects with more accurate
colors. All of AstroFX’s image-processing steps have an Auto button
that eliminates guesswork and produces excellent results.
This view of the California Nebula next to brilliant Menkib (Xi
Persei) is a stack of 21 fi ve-minute exposures with the Nightscape
attached to the author’s Nikon 300-mm f/2.8 lens set to f/4.0.
Fayetteville, N.C., newspaper photo editor Johnny Horne wonders
how much camera $1,499 will buy 15 years from now.
SkyandTelescope.com May 2012 67