Page 100 - BBC Sky at Night - September 2017 UK

100 FIRST LIGHT SEPTEMBER

FIRST LIGHT

> supply and the USB 3.0
SKY SAYS… cable. These are the only
Now add these: two ports on the camera
– there is no guide port,
1. Astronomik so an external guide
2-inch infrared- system is required for
EORFN!"OWHU! longer exposures.
After fixing it to our
2. QHYOAG-M
own 4.5-inch reflector,
off-axis guider we selected M13 in
3. QHY5L-II Hercules as our first
target and quickly
monochrome
found that our regular
camera kit
flattener/reducer
produced serious
vignetting. It did not provide a TELESCOPE CONNECTION & ADJUSTMENT RING
large enough image circle to cover
such a large chip. Once removed, the remaining The M54 to 2-inch screw-threaded adaptor/nosepiece allows the camera to be
vignetting was easily dealt with by calibrating easily inserted into a 2-inch focuser. There is an M48 thread on the nosepiece
with flat frames. Without the reducer, the scope so you can attach a filter. The angle adjustment ring allows you to get the sensor
precisely square to the image plane.
was working at f/7, so we were surprised that a
two-minute exposure seemed to be longer than
M13 stacked from 24 one-minute
required. Cutting the exposure time to one minute
exposures and then cropped to
we took 24 images of M13. Our cropped frame of
10 per cent of the sensor area
the final stacked image – showing only 10 per cent
of the original frame area – showed superb detail,
including the propeller feature.
Encouraged by this, we moved to the Iris Nebula
in Cepheus and captured 30 two-minute exposures.
Although somewhat noisy (more frames would be
needed to clean this up) the result was surprising in
that it even revealed some of the dust surrounding
the nebula. QHY has, with the 367C, produced an
outstanding and versatile one-shot-colour camera
that pushes the boundaries of definition and
sensitivity for deep space astrophotography. S

VERDICT
BUILD AND DESIGN +++++
EASE OF USE +++++
The Iris Nebula, comprised
FEATURES +++++
of 20 two-minute exposures
IMAGING QUALITY +++++
OPTICS +++++
OVERALL +++++

WWW.THESECRETSTUDIO.NET, PETER JENKINS X 3 ! The difference cooling makes can be seen in the noise

of dark frames taken with cooling system off (left, ambient
temperature) and on (right, 30º below ambient)

skyatnightmagazine.com 2017