Sky and Telescope - December 2015 - 59

TELESCOPE SPECIFICATIONS
Inﬁnity 90

StarBlast

Aperture

90 mm

114 mm

130 mm

Focal length

600 mm

450 mm

650 mm

f/6.7

f/4.0

f/5.0

Focal ratio
Weight

OneSky

11.9 lb. (5.4 kg) 13.0 lb. (5.9 kg) 14.8 lb. (6.7 kg)

Low mag.

23×

26×

Medium mag.

67×

75×

65×

High mag.

95×

Optical speciﬁcations are based on advertised data.
Weights are as measured.

Roughly aiming the Meade Inﬁnity 90 refractor is aided by using
the long handle at the back of the tripod. Targets can then be
centered with the slow-motion controls.

a wide range of deep-sky objects. I compared the scopes
side by side on speciﬁc targets and also used each scope by
itself for an entire evening to get a sense of its overall feel.
The planets are particularly attractive targets for
beginners - and challenging targets for small telescopes. Even at medium-high magniﬁcations (67× to
75×), all three scopes easily displayed the phase of Venus,
the two main belts of Jupiter, and gorgeous views of
Saturn's rings. My best views of the planets came at 95×
with the 6.3-mm eyepiece on the Inﬁnity 90, 112× with
my own 4-mm eyepiece on the StarBlast, and 130× using
the OneSky with its 10-mm eyepiece plus a 2× Barlow.
At these magniﬁcations, I could see the Jupiter's Great
Red Spot, shadow transits of its moons, and the Cassini
Division in Saturn's rings when atmospheric steadiness allowed. These features were quite obvious in the
OneSky, a little harder to pick out in the Inﬁnity 90, and
problematic with the StarBlast.
I also tried the StarBlast at 150× with the stock 6-mm
eyepiece and a 2× Barlow, but I found the scope very
hard to focus at this magniﬁcation, and I saw little
improvement over the view at 112×. One problem with
the StarBlast is that the "sweet spot" where the view is
truly sharp is relatively small, requiring you to nudge
the scope quite frequently.
At the opposite extreme, the Inﬁnity 90's view is
sharp all the way to the ﬁeld stop; the 3-element eyepieces work very well at f/6.7. Together with the slowmotion controls, this makes it very easy to track the planets. Like all fast achromats, the Inﬁnity 90 shows violet
halos around the Moon and planets, but the planetary
views are otherwise quite attractive and detailed.
Under the semi-dark skies of my country home, all
three scopes performed admirably on deep-sky objects,
given their apertures. They showed all of the Messier

objects with ease, and provided detailed views of many.
The OneSky wins the prize on globular clusters, but all
three scopes resolve a half dozen to a dozen stars in M4,
M22, M5, and M13. The Inﬁnity 90 is best for large open
clusters such as M44, the Beehive, due to the scope's
sharp ﬁeld with the stock low-power eyepiece. But the
OneSky is also superb, and the StarBlast isn't far behind.
On galaxies and nebulae, the scopes perform in aperture
order with the best views in the largest aperture.

Conclusions
The OneSky probably ranks highest among these scopes
because it provides the best overall views both of planets
and deep-sky objects. But it does require a supplementary 2× Barlow to show the planets in detail, and its
focuser works poorly with heavy eyepieces. Moreover,
each of the other scopes has advantages that might be
compelling in speciﬁc circumstances.
The StarBlast has superb ergonomics due to its rotatable tube; it's ideal for viewing from a seated position.
Deep-sky enthusiasts will also appreciate its extraordinarily wide maximum ﬁeld of view when used with an
additional 24- or 25-mm eyepiece. It's the weakest of
the three on planets, but still comfortably ahead of most
telescopes in its price class.
The Inﬁnity 90 is best for people who want quick
looks at the Moon and planets because it requires no
collimation, cools down in a matter of minutes, and
oﬀers views not far behind the OneSky's. And it's
completely self-contained, needing no table or stand to
support it. But its alt-azimuth mount isn't well suited to
browsing the deep sky.
While each of these telescopes has some ﬂaws and
limitations, they're all easy to use and a joy to look
through. Best of all, they oﬀer outstanding value for
their amazingly low prices. ✦
Sky & Telescope Contributing Editor Tony Flanders loves to
use compact, convenient telescopes.
Sk yandTelescope.com December 2015

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Sky and Telescope - December 2015

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