Canon’s 18x50s are their most
powerful image-stabilised binoculars and are widely used for astronomy. But do
they really show you more than the latest conventional big-eye models from
premium brands?
Canon 18x50 I.S. Review
High power image stabilising bino’s have a compelling
use case for astronomers, but most high-powered I.S. models are really too
small for astronomy. Canon’s own new 14x32s join similar offerings from Fujinon and Nikon in this regard: right power, wrong
objective size. Decades on, Canon’s 15x50s and 18x50s are the only
stabilised bino’s with astronomy-sized objectives (Zeiss’
ridiculously expensive low-tech 20x60s aside).
When first I tried a pair of Canon’s 18x50s I found
them of high optical quality, but compromised in terms of the image stabiliser,
which produced too many distracting effects for my liking. At the time I
assumed everyone would start making high-power image stabilised binoculars and
I could soon pick and choose. A decade later it’s clear that’s just
not going to happen.
Meanwhile, I discovered that Canon’s 12x36s have been
quietly revamped to create an excellent astronomy bino’. So I thought
I’d give the 18x50s a second look (and a thorough review on the night
sky).
At A
Glance
|
Magnification |
18x |
|
Objective
Size |
50mm |
|
Eye Relief |
15mm
claimed |
|
Actual
Field of View |
3.7° |
|
Apparent
field of view |
60.3° |
|
Close
focus |
~4m |
|
Transmissivity |
90%
estimated |
|
Length |
193mm |
|
Weight |
1180g (excl batteries) |
Data from
Canon Ireland.
What’s in the Box?
As usual with non-European brands, Canons – even
expensive ones like these - have a basic box:
Design and Build
The Canon I.S.
range, that even they describe as ‘broad’, now (early 2021) has no
less than five different lines, though all share a similar design and look:
· Large,
high-power binoculars of semi-waterproof design, with ED lenses: 15x50 and
these 18x50s
· A new line
of 32mm models featuring a different type of I.S. derived from their camera
lenses, including a 10x32, 12x32 and a 14x32 (see below)
· An
older line including 8x25, 10x30 and 12x36, which share a similar
non-waterproof design, are light weight and fairly cheap. The 12x36s are
a Scope Views Best Buy for astronomy
· Premium
10x42s which are fully waterproof, have special red-ring lenses and are mainly
aimed at birders
· Recent
small and light-weight ‘pocket’ binoculars in 8x20 and 10x20 sizes
Two smaller high-powered Canon I.S. models – 14x32 and
12x36.
Body and Ergonomics
The need to house the I.S. electronics mean these don’t
have a normal binocular body. There is no hinge – the body is just a
solid plastic ovoid with thin, smooth armour. The result is that they look like
consumer electronics, with a button on top and a battery compartment
underneath.
Even if they remind me a bit of an old Sony Walkman, both
external and internal build quality is very high, much like my Canon DSLR in
fact.
At almost 1200g, these are heavy compared to the smaller
models, though - almost twice the weight of the basic 10x30s.
Canon claim waterproofing, but given the potential for water
ingress through the battery compartment and button, these won’t be
submersion-proof like the best roof-prism birding bino’s. You should be
able to use them safely in the rain, though.
Unlike most binoculars, the non-hinged body allows these to
avoid a tripod adapter: there is a standard ¼-20 thread underneath for
attachment to a photo tripod.
Focuser
The focuser is light, precise and free of any kind of image
shift or backlash; as good as the very best in my opinion. It’s not
super-fast, but for the precision needed with optics this sharp, and at this
magnification with a shallow field depth, that’s not a bad thing. From
close-focus of about four metres to infinity is a bit over one turn. There is
plenty of focus beyond infinity, to accommodate different peoples’
eyesight, too.
In order to make these waterproof, the focusing mechanism is
(unusually for porros) internal – the focuser
moves the objectives in and out behind a sealed optical window.
You adjust dioptre (the difference in focus between your
eyes) by the traditional method: twisting the right-hand eyepiece to focus it
independently. In this case, it works smoothly and precisely with just the
right weight (on many binoculars it’s much too stiff).
Optics - Prisms
These are porro-prism binoculars (though they don’t
look like it) – the same optical design as
‘Grandad-bino’s’. But if you think that’s a bad thing,
it’s not. In general, porro prisms give slightly higher performance than
roof prisms because they transmit more light since they don’t need mirror
coatings.
Optics - Objectives
Canon claim that these objectives have a four-element design;
I’m not sure if that includes the optical window they’ve added to
the front for waterproofing.
Unlike the cheaper models, including the 12x36s and even
14x32s, these 18x50s feature objectives containing one element of special dispersion
glass. Canon refer to this as ‘UD’ (ultra-low dispersion). Some
manufacturers use labels like ‘ED’ or ‘SD’ to describe
much the same thing, whilst others confusingly call their binoculars
‘HD’ because those special lenses give a higher definition view.
The point is that one of the lens elements is made of a
special type of glass high in fluorides that gives better resistance to
chromatic aberration (false colour fringing around high contrast parts of the
view). With such a high magnification, this is pretty much essential.
Coatings are purple in hue (not the more neutral tone you get
with high-end German bino’s these days), but they are very dark and of
high-quality. Combined with the inherently lower-loss porro-prism design, these
should give very good light throughput for a bright view.
It’s worth pointing out at this stage that overall
optical quality is very, very high. There is none of the softness you get with
some high-powered binoculars. Canon make a lot of quality optics (including the
objectives for Takahashi telescopes) and that experience shows here. In terms
of sheer optical quality, these give nothing away to the likes of Swarovski,
Zeiss and Nikon.
The insides of the barrels are machined with lots of fine
baffles to kill stray light and prevent flare.
Barrels are
outstandingly well baffled against stray light.
Optics – Eyepieces
The eyepieces are a complex design that Canon state has seven
elements, including a doublet field flattener. That multi-element eyepiece
design delivers a fairly wide (for binoculars) 60° apparent field of view, that
translates to 3.7° true field width. In theory, these
eyepieces also have decent eye relief too (the distance away from the eyepiece
that the image is formed), for comfort with glasses …
Canon claim 15mm of eye relief (exit pupil distance),
measured from the eye lens. But the eye lens is deeply recessed in the eye cup
and so the effective value is more like 10mm. This means a greatly reduced field with glasses on and just isn’t
up to industry-leading standards these days.
Another problem is inter-pupillary distance. With no bridge,
these have moveable eyepieces to accommodate different inter-pupillary
distances. That’s fine, in theory, but the big eyepieces and cups will
squeeze your nose if your IPD is small, like mine.
Most premium binoculars these days have twist-adjustable eye
cups with several settings. These have the old-fashioned fold-down rubber eye
cups, that are much less adjustable and will probably eventually perish and
split at the fold point. The eye cups are sticky rubber and are magnets for
dust. They are, however, easy to fold and work well, unlike some.
Optics – Image Stabiliser
The
biggest problem with high-powered binoculars is that the extra magnification
amplifies your shakes as well, blurring the view and making it harder to see
fine details. These can be used without stabilisation, just like normal
binoculars, though 18x really does magnify hand-held shakes a lot. So,
you’ll mostly use them by activating their image stabilising function.
The
image stabilisation employs a microprocessor to detect movements and then alter
what Canon describe as a ’vari-angle
prism’ to counteract them in real time. Most of Canon’s I.S.
bino’s work this way, but not all. Canon’s most recent models, like
the 14x32s, have a dual-I.S. system that changes the offset between lenses
instead of the flexible prism. This new system is derived from their cameras
and is supposed to be higher fidelity, though my review of the 14x32s
didn’t convince me it was significantly better.
Other
manufacturers have image stabilising binoculars which use different systems,
like gyros to simply resist the shaking, or with gimbled prisms.
Like
other Canon stabilised binoculars, you activate the I.S. system on these 18x50s
by pushing a button. The button is quite deeply recessed and takes a firm push,
but an audible click and a green light confirm the I.S. is active. Alternatively, you can give it a
lighter push, in which case the I.S. is active only until you release the
button again.
The first pair of these I tried, many years back, had pretty nasty
I.S. with lots of unpleasant artefacts: the focus point faded in and out;
colours jazzed; panning was jerky. These are much better; on first look, the
I.S. seems virtually flawless: the image just steadies very positively and
effectively. There is little noise and panning works fine too.
However, there are still downsides to the I.S. on these,
Canon’s most powerful model, that lower-powered ones like the 12x36s
avoid:
1)
The
I.S. can take quite a few seconds to really settle and deliver full resolution.
Until then, one or both barrels can be blurred as if defocussed slightly,
leaving you twiddling the focuser in frustration. Meanwhile, it’s as if
the optics are poor (they’re not, the effect wears off after a while if
you hold them reasonably steady). This initial defocus is very noticeable on
the Moon, stars and planets, but on daytime landscapes, too.
2)
Too
much shakes can re-introduce that blurring, until you and the system settle
again. This means getting and retaining a perfect view for long periods can be
difficult.
3)
In
use, the I.S. will occasionally make a clicking noise, or suddenly jerk the
view about a bit, if you stress it with too much shaking.
Overall, the I.S. works well though.
Hold them steady and you are (eventually) rewarded with an impressively sharp
and stable view; rest on something and the view is telescope-steady.
Accessories
The 18x50s have a plain Cordura soft case, a basic strap with
quite thin webbing and press-on eyepiece caps only. The case is annoying
because the catch looks particularly fragile. Binoculars this costly deserve
better.
In Use – Daytime
Ergonomics and Handling
Handling is the only area where these are noticeably worse
than most current premium binoculars. That fat, bridgeless body is harder to
hold than nicely sculpted barrels and the armour feels thin and less grippy
than the best. That said, the focuser is superb and the dioptre adjustment
simple but effective.
Weight is similar to most 50mm binoculars, although they do
get tiring to hold up after a while when compared to lightweight 10x42s, for
example. They do feel much heavier than some of the smaller models, like the
12x36s and 14x32s.
It’s the eyepieces that are the main comfort problem.
For me they are not really comfortable with my specs off and balanced on my
nose (or squeezing it), but they don’t have enough eye relief to show
much more than about half the field with glasses on.
In my opinion, these are not an attractive-looking pair of
binoculars. If you want a certain sartorial panache to your bino’s, then
you’ll need to look elsewhere (perhaps Leica’s beautiful
leather-armoured models).
The View
Considering their high magnification, these give a very
bright, sharp, high-contrast daytime view. You often do need to wait for a few seconds
for the view to stabilise fully and reach maximum sharpness after you engage
I.S., though. The field is wide and focus snap absolute, though the depth of
field is very shallow (something to be expected with a high magnification) and
so you do need to use the focuser a lot.
The high magnification, superb optics
and stabilisation mean that these 18x50s resolve more than almost any other
hand-held binoculars.
That high power and steady view allow you to identify birds
at extreme range. I managed to ID a Kestrel soaring a kilometre or more off,
just a speck with the naked eye. I watched a pair of Jackdaws mobbing a Buzzard
hundreds of metres away. They would be a valuable addition to a birder’s
kit-bag, for when a scope isn’t possible or available.
The 18x50s’ capabilities don’t stop with birding
either. I tracked a Hawk fighter aircraft headed out over the Lake District
from miles away, an extreme range to be able to make an ID, much further than
any other hand held would have allowed. These would work very well for plane
spotters.
For other kinds of daytime spotting, marine use, or nature
viewing, these again show you more than any normal hand-held binoculars:
looking across the bay to Morecambe, eight miles away, I could see individual
houses, cars and trees, that are normally just vague impressions with other
binoculars.
Flat field?
These Canons are advertised as having field flatteners and
indeed the field is very flat for binoculars, one of the very flattest I have
tested - largely free from astigmatism and curvature and with just a little
distortion. Even the field edge is completely usable.
Chromatic Aberration
When discussing chromatic aberration, we have to consider
that 18x is a very high magnification for binoculars (false colour worsens
dramatically at higher powers, given the same optical design). So, yes, there
is false colour: you can easily see it on silhouetted birds or branches,
especially when focusing through - a purple tinge one side of focus, green the
other.
In general use, false colour isn’t a problem, though.
Watching my local Jackdaws in silhouette against a dusk sky, huddling in pairs
and settling into their high branches for the night, is particularly easy with
these, slight colour fringing notwithstanding.
Like most high-power designs, these suffer from an increase
in chromatic aberration near the field edge, but it’s not as bad as some
and rarely intrusive.
In Use – Dusk
These
penetrate dusk shadows well, due to their high magnification, steady view and
bright porro-prism optics.
In Use – The Night Sky
Canon (unusually) list astronomy as one of the possible uses
for these 18x50s, so I will spend some time reviewing these on the night sky
– object by object – but I will start with some general
observations.
Once the I.S. has settled down, Vega yields nice round,
concentric rings either side of focus – a sign of excellent binocular
optics (even though the power is a bit low for a ‘proper’ star
test).
Stars remain points right to the field stop. These
don’t have a significantly curved focal surface or much off-axis
astigmatism (that turns stars into blobs or lines, respectively), unlike many
bino’s. That doublet field flattener does a good job of making these one
of the flattest-field binoculars of all, a great feature for astronomy.
The field of view is good for the high magnification, at 3.7° true. It’s enough to encompass more or less any region
of sky you might want to view. Whilst the area left by the vignetting you get
wearing glasses is smaller, it’s not as much of a problem at night and
still leaves enough sky area to fit in Orion’s sword region, for example.
Nonetheless, these don’t give the gorgeously wide star fields that fine
10x50s do.
There is some faint ghosting with a bright light in the field, but that careful baffling
means that working around bright
lights is never a problem – good news for urban users.
One trick I learnt with these is to look for things by
panning slowly with the I.S. enabled
– the steadier view makes finding fainter objects easier.
The Moon
One day past full and pressing the magic button yields a host
of craters – including dark-floored Endymion and Mare Humboldtianum
behind it - along the terminator in superb, sharp detail … eventually. At
first, though, the view is slightly soft and fuzzy. I have to wait for perhaps
twenty seconds for the I.S. to settle down and the view to sharpen fully.
Thereafter, a final tweak of the focuser (the sweet spot is very small)
delivers a view like mounted binoculars.
On day four of the next lunar cycle, elbows resting on the
roof of my car for a bit of extra support, I again get a telescope-like view
with all the major features easy to pick out. The bigger craters, like
Cleomedes, Langrenus and Petavius
are easy, but I can make out smaller ones too - Picard in Mare Criseum and nearby Proclus with its bright rays; Stevinus, Snellius and Geminus on the terminator, floors full of
black shadow. The view is perfectly sharp and full of contrast and detail, with
only a little false colour around the bright Lunar limb to complain about.
I would buy a pair of these Canon 18x50s if I lived in the
suburbs with nowhere to set up a scope, even if only to enjoy the Moon. Once
settled, these give Lunar views much more like a telescope than any other
hand-held binoculars. Most of the features in my ‘Photographic Atlas of
the Moon’ are within its grasp and that steady view makes the Moon really
explorable.
Venus
Venus in a dusk sky showed a little flare until the I.S. had
settled for perhaps 20-30s, then almost none. Venus’s brilliant white
gibbous orb, at 19” across, was then very easy to make out, by far the
best view of it I have had with binoculars. This is impressive – more
than a few spotting scopes struggle with Venus.
Jupiter
With the usual caveat about waiting for the I.S. to settle
down, the view of Jupiter was outstanding for binoculars. The planet appeared
as a perfect disk, an unexpectedly large one due to the high magnification.
There is no spiking or smearing at all. In a brightening dawn sky that lowers
the contrast a bit, I could even make out a hint of the equatorial belts, a
rare ability in binoculars. Jupiter’s Galilean moons were super easy to
track with these.
Mars
Of course, these aren’t about to show you albedo
marking on Mars, but even six months after opposition, when it’s very
small, Mars is still obviously a planet – bigger than the tight Airy disk
of a similarly bright star.
Deep Sky
For small DSOs, the Canon 18x50s are a winner. The Ring
Nebula (M57) is easier to find than with any other hand-held binoculars
I’ve tried. Similarly, the Dumbbell isn’t as bright as through
big-eye 56mm binoculars (which gather 25% more light), but shape and definition
is outstanding, really picked out from the background by the steadying effect
of the I.S. The Crab Nebula (M1) is again easier to pick out than usual and
shows its shape better than in any lower-powered hand-held binoculars. Bode’s
Nebula, big and clear through the 18x50s, also shows more of the shape and
character of its two constituent galaxies. What’s more, the high
magnification supresses sky glow and haze, helping find smaller DSOs.
Globular Clusters are easy to find and look good too; M15,
right of star Enif in Pegasus, looked like a properly
fuzzy star, albeit a bit dimmer than through a good 15x56. Smaller, but still
obviously a globular, is M56 between Cygnus and Lyra – quite hard to find
in smaller bino’s but easy with these.
The sword area of Orion, with big and bright M42, looks
‘telescopic’ through the 18x50s, with the four main Trapezium stars
easily resolved. The nebula is big and bright and shows a lot of detail,
especially with averted vision; I can see hints of whorls and the
‘arms’ and central ‘spike’ of nebulosity spreading a
long way into space. Still, the smaller aperture means I can’t see hints
of colour as well as with 15x56s under dark skies.
The news is also positive for open clusters. The Starfish and
Pinwheel clusters in Auriga aren’t as bright as through 15x56s, but show
all their bright constituent stars and their very recognisable shapes in a way
lower powers and non-I.S. just don’t permit. The Double Cluster similarly
isn’t as bright as through 15x56s, but it’s easier to see
individual stars within it.
On the downside, I did notice that fainter galaxies are a bit
harder to find than through 15x56s, whilst M31 is just too big for the smaller
field of these.
Overall, the flat field, high
magnification and I.S. make these a superb astronomy tool that excels on the
Moon and small DSOs. But lack of aperture means a bit less reach than fine
15x56s and nebulosity sometimes looks less bright and detailed as a result.
Canon 18x50s’ 3.7° field of
view on Orion.
Satellites
One possible interesting use for these is hunting and
watching satellites. They have the useful property of telescope-like
resolution, with binoculars’ ability to pick up and track fast-moving
objects. I watched a bright satellite (perhaps some Cosmos flavour) cross the
sky, sweeping to follow it with the I.S. (no pun intended) engaged, and I could
make out its cross-shape, formed by the fuselage and solar panels.
Testing the
Canon 18x50s.
Canon 18x50 vs Zeiss 15x56 Conquest
HD
The discounted price of these binoculars is very similar.
Both offer outstanding value for hand-held astronomy and are obvious
competitors. So how does the German engineering and bigger aperture of the
Zeiss stack up against the higher power and image stabiliser of the Canons?
· Weight is similar, but the Canons are
more compact
· Optical quality is similar
· Chromatic aberration levels are
similar
· The Zeiss Conquests have more eye
relief – a big factor if you wear glasses
· The Zeiss have a wider field, but the
Canons’ is more perfectly flat
· The Zeiss give a wider field for
panning through star fields
·
The higher magnification and I.S. make the Canons much better for the
Moon and smaller DSOs, able to resolve detail no normal hand-helds can
That last is the killer app here. If you live under urban or
suburban skies with nowhere to regularly setup a telescope, or if you value
super quick-looks between the clouds, get the Canons.
Summary
The first thing to say is that image stabilisation is no
gimmick and works well, delivering way higher resolution than any normal hand-held
binoculars can, especially at this high magnification. The basic optics are
first rate too, giving a flat, sharp, bright and very wide field. No issue with
the focuser either, it’s smooth and precise.
Make no mistake, the resolution of these is a big deal. For
very long-range birding, exploring the Moon, or perhaps checking out the secret
aircraft on the Tonopah Test Range in Nevada from that hill south of Highway 6
(sorry, Mr CIA Man, Sir, I was just kidding), these outperform everything else:
no conventional binoculars are going to reveal as much without a tripod.
So, the image stabiliser really works, but it does take a
long time to settle and can occasionally make the view jerk around or
temporarily blur whilst in use.
There are other issues, too. The biggest is with the
eyepieces. There isn’t enough eye relief to see anything like the whole
view with glasses and the eye cups are the old-fashioned roll-down type. More
problematic for some people is that the eyepieces are too fat and pinch your
nose, if you have a small inter-pupillary distance, like me; you can get around
this by folding the eye-cups down and kind of resting them on your nose, but
it’s not ideal. Another small issue is that the depth of field is very
shallow – you have to re-focus a lot when you pan around during the day.
Though the build quality is high, these are a bit plasticky
compared to a fine conventional binocular of similar price. You should also
consider that these are essentially a piece of consumer electronics -
they’re not an heirloom the way those Swarovskis,
Zeiss or Leicas could be.
But here’s the thing: if you need the highest resolution in a hand-held binocular – for
birding, spotting or astronomy – these deliver like nothing else.
Do you really need a scope, but don’t have the time or
space? You just found the best solution currently available. Canon’s
18x50s are very highly recommended, if you can live with their downsides.
You can buy the similar 15x50IS Binos from Amazon here and give ScopeViews a bit of commission towards new content!
OR Buy Canon 18x50 IS from Wex here:
