MAKSUTOV NEWTONIAN.
Although many observers would say
that the very best images come from apochromatic
refractors, this
may only be true up to 5” or 6” beyond
which size, the sheer complexity and cost of producing
the many accurate surfaces from completely distortion
free glass conflicts with the desire for greater
aperture and a more compact design. Enter the Maksutov
Newton.
This design although developed in
the 1940's was popularized in
the 90's and has gained
much acceptance since. Similar in appearance to
a Newtonian reflector, the presence of the Mak
Newt
corrector plate reduces the troublesome tube currents,
coma and diffraction spikes experienced with a
Newtonian reflector. The size of the secondary
is in many
cases smaller. The Mak Newt offers a larger flatter
field of view than a comparable Newtonian or Mak
Cass and the smaller central obstruction yields
images every bit as good as the best apochromatic
refractors
in the world at a fraction of the cost and in a
more compact form. The cost of owning an eight
inch
or larger apo is beyond the means of most enthusiasts,
as is the cost of the mount to hold it. Some of
the best views that can be obtained from Earth
especially
of the Moon and Planets can be seen through a Mak
Newt.
The
central obstruction is typically around 20% (on
a diameter comparison) or less and is
largely responsible
for the sharpness, contrast, colour and clarity
of the images obtained. The downside is that
the shorter
back-focus available on most Mak Newts, means that
additional lenses will have to be used to bring
the focus to a point where binoviewers can
be used. The shorter F ratios
yield magnificent wide field views and good quality
barlows can be
used such as a 4x Powermate for the additional
magnification for planetary studies without
any loss in sharpness
of the image. A slightly larger mount will be required
to compensate for the longer tube and should be
sturdy enough to overcome wind effects if
imaging is a priority.
Stellar Optical Corp currently stocks
the five Maksutov Newtonian telescopes
listed below, but hopes to be able to add more
in the future.
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