Sky & Telescope - September 2024 - 66

S&T Test Report by Richard S. Wright, Jr.
Sky-Watcher's 6-inch Astrograph
This fast Newtonian reflector offers generous aperture at an attractive price.
Quattro 150P
U.S. Price: $595
skywatcherusa.com
What We Like
Included corrector/reducer
Solid focuser
What We Don't Like
Small knobs rust in humid
conditions
Shiny spots in optical path
cause scatter
A QUALITY NEWTONIAN reflector is
without question the most cost-effective
way to get into astrophotography.
A Newt produces images inherently
free from chromatic aberration and
offers a generous aperture in a relatively
compact design. I own a 12-inch
Sky-Watcher Quattro 300P Newtonian
reflector that I've enjoyed using for
years, and when I first saw the 6-inch
150P last year at the NEAF trade show,
I thought it an adorable baby version of
the behemoth I had at home - a scope
my wife affectionately calls the " big
black garbage can. " So, I was looking
forward to trying out the 150P on loan
from the manufacturer for this review.
The Included Gear
The Quattro 150P is the smallest model
in Sky-Watcher's Quattro series. Quattro
means " four " in Italian and is a
fitting moniker for the company's line
of f/4 Newtonian astrographs, which
are now available with apertures of 6,
8, 10, and 12 inches (150, 200, 250,
and 300 millimeters, respectively). The
tube of the 150P is rolled steel with a
glossy, metal-flake finish on the outside
- just like its larger siblings. The inside
66 SEPTEMBER 2024 * SKY & TELESCOPE
Sky-Watcher's Quattro 150P is a 6-inch f/4
Newtonian reflector that comes with a 6 × 30
finderscope, a photographic coma corrector/
focal reducer, 2-inch and 1¼-inch extension
adapters, and a 1¼-inch, 22-mm wide-field
eyepiece. Also included are the tools needed
for collimating the secondary mirror.
is painted flat black, and, unlike in the
larger models, there are no ring baffles
to reduce scatter in the tube.
The 150P's primary and secondary
mirrors are made from borosilicate glass
with Sky-Watcher's proprietary Radiant
Aluminum Quartz coatings, for which
the manufacturer claims 94% reflectivity.
Its 2½-inch secondary mirror is
designed to illuminate a large field of
view. Paired with the included coma
corrector, Sky-Watcher states it produces
a corrected field ideally matched
for APS-C sensors. The instrument's
native focal length is 600 mm, though
the included coma corrector/focal
reducer shortens it to 518 mm, resulting
in a photographically fast focal ratio of
f/3.45. That's impressively fast - two
full f-stops better than an equivalent
150-mm telescope operating at f/7.
The scope has a 2-inch, dual-speed,
Crayford-style focuser with 11:1 reduction.
It also includes a 2-inch extension
tube and a 1¼-inch custom eyepiece
adapter, both for visual use. The Quattro
150P comes with a 1¼-inch, 22-mm
ultra-wide eyepiece having a 70°
apparent field of view that is quite nice.
The eye relief isn't listed, but I found it
comfortable to use.
A finder shoe is located next to the
The dual-speed Crayford focuser held its
position reliably even with heavy cameras and
when pointing in any direction. The fine-adjustment
knob is adequate for manually focusing
even at f/3.45.
focuser to accommodate the included
6 × 30 finderscope. Imagers should
note this is a great place to mount a
small guidescope and autoguider combination.
ALL
IMAGES COURTESY OF THE AUTHOR
http://www.skywatcherusa.com
Sky & Telescope - September 2024

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