WWW.ASTRONOMY.COM 55well capacity. If your cam-
era has a shallow deep well,
bright stars will quickly turn
pure white and lose their
color, and even bright nebulae
can appear washed out. To
avoid this, I typically set my
offset to 25 and reduce my
gain to a low setting or even
zero. The 410C has a deep
well of 120,000 binned 1 by 1
in a low-gain setting. Typical
deep wells, meanwhile, range
between 25,000 to 75,000.
My exposure times
depend on the telescope and
the brightness of my target. I
typically shoot RGB one night
and, if needed, narrow band
the next. The RGB exposures
are usually between 10 and 20
minutes with an f/7 telescope.
I double the exposure time
when using a narrow-band
filter. For the technically curi-
ous, the QHY 410C has only a
trace 1.6-electron read noise
at low gain and a dynamic
range of more than 14 f/stops.
The camera’s chip has large
6-micron pixels that are very
good at recording faint levels
of light during long exposure
shots. It is, to date, Sony’s
most light-sensitive CMOS
chip.
The camera also has a two-
stage thermoelectric cooler,
and QHY employs unique
thermal noise-control tech-
nology to reduce noise to a
very low level, all without
affecting the raw data integ-
rity. This is obvious when you
see the results: There is zero
amplifier glow, no matter how
long the exposure.
The windows of theThe Veil Nebula, an ionized cloud of gas and dust, highlights how beautiful the
tattered remains of an ancient supernova can be. The author captured this
view in the fall of 2021 using the QHY 410C. Technical details: one set of nine
10-minute subs binned 1 by 1 (in RGB to get the color of the stars), gain=0,
offset=50; a second set of nine 20-minute subs (taken with an Optolong
L-eXtreme filter to capture nebulosity), gain=50, offset=50; images deBayered
and combined in AstroArt; stretched and processed in Photoshop CS 6.VEIL NEBULAchamber are constructed to
prevent dewing in wet condi-
tions, as well as AR+AR
coated to reduce ref lections.
The drivers for the camera
have been time tested and
work f lawlessly. In fact, so
far, I have never had a single
problem with this camera.The QHY 410C can do a
lot of imaging, from RGB to
narrow band. Color cameras
like this alleviate some of the
challenges that crop up when
using mono cameras. They
are also usually cheaper and
lighter than their mono coun-
terparts. All you need is a fil-
ter slide drawer and a filter
holder so that you can swap
in UV-IR and narrow-band
filters as needed.
A camera as powerful as
the QHY 410C would have
been unimaginable 10 or even
just five years ago. Back-
illuminated chips were once
only the stuff of research labs.
But now, they are readily
available to the consumer. So,
when you own a QHY 410C,
you’re owning the next big
step in imaging technology,
as well as helping usher in the
arrival of the CMOS chip as a
mainstay in astroimaging.MY EXPOSURE
TIMES DEPEND ON
THE TELESCOPE
AND THE
BRIGHTNESS OF
MY TARGET. I
TYPICALLY SHOOT
RGB ONE NIGHT
AND, IF NEEDED,
NARROW BAND
T HE NE X T.Tony Hallas is one of the world’s top astroimagers.