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ABOVE: Emission nebula
NGC 281 in Cassiopeia
shows lots of detail in
this image taken through
R, G, B, Hydrogen-alpha,
and Oxygen-III filters.
TONY HALLASFAR LEFT: QHYCCD’s
new camera, the QHY
600, incorporates a full-
frame CMOS chip that
produces 61-megapixelfirst autoguider that actually worked: the images. QHYCCD
SBIG ST-4. It immediately changed
everything. Imagers could digitize film
using a scanner and then process the
image on a computer using an early (and
now considered crude) version of
Photoshop. After that, the first CCD
(charge-coupled device) cameras became
available. They were tiny things, some
smaller than a postage stamp.
At first, CCD images were a curiosity,
certainly no match for
hypered — sensitized by
a gas — large-format film
images exposed through superb tele-
scopes. But little by little, CCD technol-
ogy improved. What finally elevated it
above film was its quantum efficiency.
With film, you were lucky if it
recorded 3 to 5 percent of the light that
fell on it. With a CCD, that number bal-
looned to over 50 percent. Suddenly,images were being made
that were not possible just a
year before, and amateur
astronomers were capturing new details
on familiar objects for the first time.
Soon after the CCD appeared, another
new detector arrived: the CMOS, short
for complementary metal-oxide semicon-
ductor. Unlike a CCD, where data is
downloaded in rows and read at the edge
of the chip, a CMOS chip reads every