Swarovski 15x56 SLC Neu Review
A magnification of 15x is my favourite for
astronomy. It gives a binocular almost telescopic abilities to find and see
faint objects and detail. The problem is that the choice of hand-held binoculars at these
magnifications is limited, because their market is mostly limited to hunters
and plane spotters. Worse (for manufacturers) the high power puts a strain on
the optics that lower powers don’t, so high-power binoculars require particular
care in design and construction to avoid unsharp optics
and too much chromatic aberration (try a cheap pair of 12x50s and you’ll see
what I mean).
I have already reviewed two of the
handful of quality 15x binoculars under 1.5kg: the Minox 15x58
and the Leica 10+15x50 Duovids. The
obvious remaining premium contender in this category are the binoculars on test
here – Swarovski’s 15x56 SLCs (Habichts).
Note:
This model has been superceded by an HD version that is smaller, brighter and
has less chromatic aberration. I’ve reviewed it elsewhere on this site.
At
A Glance
|
Magnification |
15x |
|
Objective
Size |
56mm |
|
Eye Relief |
13mm |
|
Actual
Field of View |
4.4° |
|
Apparent field
of view |
64° |
|
Transmissivity |
~85-90%
est. |
|
Dimensions
(L x W) |
205mm x
130mm |
|
Weight |
1290g |
What’s in the Box?
The 15x56 SLCs as they came back from
repair by Swarovski – like new!
Design and Build
Swarovski produce two ranges of
roof-prism binoculars – the premium ELs and the second-rung SLCs (Habichts). The latter has a much bigger range of sizes,
from 8x30 to their largest model, the 15x56, reviewed here, via various 8x42s,
7x50s etc. The SLC range was updated a few years ago to appear as the
“SLC neu” (“neu” means
“new” in German for those in doubt).
All the SLCs are conventional
roof-prism binoculars with modern features such as dielectric prism mirrors for
high light throughput and the best modern coatings. However, until recently
none had the all-important HD lenses (containing high-fluoride glass) that the
new ELs do. However, Swarovski recently launched an HD version of the SLC, but
only in the two mainstream 42mm birding sizes. The rest of the SLC range still
has to make do with outdated lens technology and no surprise there – one of the
problems with high power binoculars is that they always lag behind the
technology curve due to their small market.
Body
and Ergonomics
The
15x56s are the largest SLCs and in photos they look just that: big.
Now for me big is bad in binoculars. Indeed, the 15x58 Minox were
too big, so that (if nothing else) they looked at the same time ridiculous,
nerdy and slightly menacing hanging around my neck on a Sunday afternoon
stroll. So imagine my surprise to find that the 15x56 SLCs are really quite
small in comparison. The 15x56 SLCs are still much larger than say a 10x42. But
though they are long, they are not much wider than a pair of ELs. They are quite
heavy, but 1290g is modest for a 15x56, especially when you consider that these
are all-aluminium, not lighter magnesium (ELs and Leica HDs) or
composite (Zeiss FLs). The 15x56 SLCs are hand-holdable for
me in a way that 1.5 Kg plus binoculars just aren’t. Below are some photos of
the big SLCs next to other binos for comparison.
Overall external quality of the SLCs is
high – similar to the ELs in fact. There is nothing to suggest that these are a
budget model (don’t imagine that these are to the ELs what Nikon’s Monarchs are
to their HG or EDG ranges, for example). The dark green armour is also
identical to the ELs and is quite attractive, though more functional-looking
than a Leica (these aren’t as pretty as the Duovids). The
SLCs have deep thumb depressions on the back to help with holding, which is
good, because there is a downside to the slimness Swarovski have achieved with
these – there isn’t enough space between the barrels in use (with my eye
spacing anyhow) to get my fingers between those long barrels between the
objectives and the bridge.
Other external features of the SLC
include provision for a tripod adapter (more on that in a separate section
later), single-position twist-up eyecups and a big central focuser knob (all
things you would expect).
The SLCs are nitrogen filled and
waterproof to 4m, as with any premium roof bino’.
Focuser
The focuser on
the SLCs is swift and smooth, taking just over a turn lock-to-lock. A little
stiffer than the EL’s, the SLC mechanism doesn’t suffer from occasional
stickiness in the same way and I’m not sure I don’t prefer it. Dioptre
adjustment is different from the ELs too, by an inset knob on the front of the
main one that you have to push-in to turn and it too works well.
Swarovski
15x56 SLCs alongside 10x42 ELs .
Swarovski
15x56 SLCs next to Nikon 12x50 SEs
Swarovski
15x56 SLCs and 12x50 ELs.
Optics
You could characterise the body of the
SLCs as “high quality, but conventional” and the optics are much the same. The
objectives are probably a triplet tele-objective design, but as I said at the
start, they are not HD (i.e. they don’t contain high-fluoride glasses to reduce
chromatic aberration.) The coatings look good – much the same as the ELs. The
lenses are well recessed and the internals show some evidence of baffling (but
not the exquisite knife-edge baffles you get in a Leica). The prisms have
phase coatings, as you would expect on a modern roof-prism and also have the
latest dielectric prism coatings, so brightness should be good.
The 56mm objectives fill the barrels,
which are barely 3mm thick including the armour. If you question whether 56mm
objectives are a big deal over 50mm ones, consider that they give 25% more
light gathering power. This won’t be noticeable during the day, but certainly
will for astronomy, owling, or night hunting.
Eyepieces
The eyepieces look conventional, with
normal sized 18mm diameter eye-lenses, rather than the massive Nagler-like eye lenses on the new ELs. Eye relief is a
rather tight 13mm from the eye-cup, just as claimed. Field of view for the
15x56s is 64° apparent translating to about 4.4° actual field width –
both good for a high-power binocular.
The eye-cups are the usual top-quality
Swarovski items with a single click-stop extension.
Accessories
The
15x56 SLCs have a basic black cordura case with a
hawk logo common with the rest of the range and with the Habichts
too. These larger SLCs have the ‘lift’ padded strap that makes length
adjustment a bit easier. A 2x booster is available for these 15x56s that screws
in place of one of the eye cups (see separate review). The booster has a narrow
field of view, but otherwise works well, turning these into a 30x scope of high
optical quality.
Tripod
Adapter
Instead of some contraption of bungy straps like the adapter for Leica’s Duovids, Swarovski have developed a superb tripod
adapter for the SLCs; it works like this: You
remove the penny-sized cover at the front of the binocular hinge and replace it
with a small lug that has an Allen bolt to secure it. This lug is unobtrusive
and can be left in place permanently. The adapter is a slim and elegant pillar
that slips between the barrels and mates with the lug. Tightening a clamp grips
the lug securely from all sides and the binoculars are ready to mount on a
photo tripod, either with a ¼-20 thread on the adapter base, or better by
slipping the base of the adapter directly into the dovetail shoe.
Once
mounted with the tripod adapter you can fit the 2x booster to make a 30x scope.
In
Use – Daytime
Ergonomics
The
SLCs are small and light enough to wear for an extended period and without
looking too odd when out walking. That’s the real benefit that you are paying
for – you simply couldn’t do that with many big-eye binoculars.
The
slim design of the SLCs mean you can’t wrap your fingers around the barrels,
which makes my favourite way of holding high-power binos difficult
to achieve comfortably. I like to hold around the barrels because this reduces
shakes a bit and shakes are the big enemy of any hand-held high-power
binoculars. The deep thumb recesses are a nice effort, but they mean you have
to then rest the barrels on your palms with your elbows forwards – not a very
comfortable choice for me.
The shortish eye relief means that without glasses the
single position on the eyecups is too far away from the eye lens and I would
prefer an intermediate position (Leica’s 12x50 HD with the same 13mm ER
has an intermediate position which works well).
The
View
I
looked through the SLCs for the first time straight after using the 10x42 ELs:
big mistake. After the ELs, the most noticeable things about the SLCs were the
short eye relief and the higher levels of chromatic aberration. Having got used
to those things, the view started to look a lot better.
The
main thing to say is that the 15x56 SLCs have none of the optical softness that
spoiled the Minox 15x58s. Swarovski have
clearly taken care to make all the lenses smooth and accurately figured, with
fine assembly tolerances, as high-power binoculars require. For the view is in
fact very sharp indeed, with excellent resolution across most of the wide field.
These pull distant things really close and show a lot of fine detail. Often,
you only remember you are using 15x when you pull them away from your eyes and
the thing you were viewing disappears back into the far distance.
Best
focus is a very precise point in both barrels and requires the smooth and
accurate focus action to obtain it. No hunting for best focus is ever required
and when found it applies across virtually the whole view. Another benefit of
this optical precision is the ease with which you can exactly adjust the
click-stop dioptre setting to perfectly match your eyes.
Brightness
is good considering the high power, much better than the Minox 15x58s and on a par with the Leica Duovids, but not quite up to the best levels
(i.e. Zeiss FLs). I should point out again here that daytime brightness
with these is not helped by the 56mm lenses, because the eye’s contracted pupil
effectively stops them down to be something like 15x40s. Rather, daytime
brightness is controlled by the transmissivity of the lenses and prisms.
The
field of view with glasses on is narrow and not very comfortable. Swarovski
state 3° when used with glasses and that’s probably about right. It’s amazing
the difference between 13mm and 16mm of eye relief and I am again left
wondering why customers with glasses should suffer this way for the sake of an
extra 3mm, especially at the premium price. For those who view without glasses
the news is good because the 15x56 SLCs have a generous apparent field with
good flatness that delivers a very pleasant daytime view for such a high power.
When
reviewing other premium binoculars with HD lenses, such
as Zeiss FLs, Leica HDs etc, I have
spoken about “residual chromatic aberration”. I use this phrase because those
binoculars control CA well (much better than most), but look at the same view
at the same power through a small apochromatic astro’
scope and you realise that CA is certainly still present in those binoculars if
you go looking for it. Older, pre-HD designs like these SLCs, have significant
chromatic aberration.
Update: When I first reviewed these binoculars
their CA levels were excessive and I said so. However … a few years later I had
to send them back because the seals had gone in one of the barrels. Swarovski
re-built them and lo and behold, CA levels were now not nearly as bad as they
had been.
Chromatic
aberration is now at a similar level to other premium, non-HD binoculars, not
much worse than Nikon’s excellent 12x50 SEs for example. Yes, when looking at
birds in tree branches on a bright overcast day you do get a thin purple or
green edge around feather and branch that you don’t see with the latest HD
designs. But in general, even during daytime, chromatic aberration is no
spoiler with these binoculars.
Overall, daytime performance for a high-power
binocular is really excellent – sharp, wide and quite bright. These
emphatically don’t have the dim fuzzy views you often get with higher-power binos.
This
snapshot taken through the 15x56s gives an impression of the excellent centre-field
sharpness, but also some chromatic aberration in these very bright conditions.
In
Use – The Night Sky
The paradox of these binoculars is that
they were undoubtedly designed for daytime use – primarily for hunting – yet
they are at their very best when used for astronomy.
The combination of high power, high
optical fabrication quality, good transmissivity and big objectives are a
killer combination for astronomical use. The effect is very different from
smaller, lower-power binoculars, even superb ones like the 10x42 ELs. That old
saw “size matters” was never more appropriate. These show you a lot more.
However, a note of caution: these are
still big heavy binoculars and combined with high-power accentuated shakes,
they are more tiring to use than smaller, lower-powered models. The 15x56 SLCs are not a general purpose
binocular in a way that 10x50 or 12x50s can be. Try before you buy!
The Moon
I like looking at the Moon with
binoculars because you get more of a sense of the whole Moon and can enjoy the
romance of watching it drifting through rainbow-coloured ice clouds or rising
over a snowy winter forest. What’s more, I can’t see the Moon from my
observatory before about Day 6 of a lunation. So I need binoculars that work
well on the Moon and the big Swaro’s do
just that.
A magnification
of 15x crosses some kind of threshold when viewing the Moon: you can
see all the major craters and mountain chains in a way you can’t with lower
powers. You really need to rest against a wall or on a car roof at this power,
but if you do the super-sharp optics deliver a sensational view. Buy a Moon
atlas and you could use these to explore many of the features it contains. When
tripod-mounted, the big SLCs really show off their optical quality with a view
that is very similar to a good small refractor: perfectly sharp, detailed
and contrasty with very good resolution.
Some chromatic aberration is present, but it remains confined to the bright
limb and doesn’t spoil things.
The Full Moon is a good test of
ghosting in-field and flare when just outside it. These are areas where “Alpha” binos often excel and the 15x56 SLCs are no exception.
Both aberrations are almost perfectly controlled – a major bonus when working
around streetlights too.
Deep Sky
Deep sky objects are where these
big-eye binoculars really excel, though. The Dumbbell Nebula is easy to pick
out, even in strong Moonlight and is clearly hour-glass shaped. The fainter
clusters, like those in Auriga, resolve into masses of stars, patches of smoke
no longer. Other more challenging binocular objects are an easy find: the Ring
Nebula, the Crab, M56 and more.
Autumn globular clusters – M15 and M2
off the end of Pegasus, M13 and M92 in Hercules – look especially interesting
and are clearly not just the ‘faint fuzzy stars’ most binoculars show.
But perhaps it is M42, the Orion Nebula,
which really shows the 15x56s off best: big, bright and detailed with lots of
nebulosity and the Trapesium resolved, but
still with whole sword region and some of the belt for context. On a dark
night, Orion has a real ‘wow’ factor through these.
There is still enough field width to
enjoy star fields and The Pleiades look beautiful with pin-point stars across a
flat field. The outstanding optical quality gives stars that are small,
sparkling and natively colourful – Albireo shows off its colours through the
15x56 SLCs.
Planets
As with any prismatic optics, these are
not planetary instruments! However, Jupiter’s disk is perfectly round with no
spiking whatever and when tripod-mounted I believe I can see a hint of the
equatorial belts. The Galilean Moons are perfect pin-points and can be resolved
even when very close to each other or just emerging from occultation. Venus is
very bright and some unfocussed light spoils the view as it does with any and
every binocular. Saturn shows a clear “handled” shape as Galileo drew it; move
your eye around and you can just make out the rings.
All-in-all astronomical performance is simply
outstanding for hand-held binoculars.
Summary
The 15x56 SLCs are a rarity amongst
high-power binoculars: they give very sharp and high-resolution views across a
wide field. Even brightness, often a bugbear with high power binos during the day, is good. Yes, they could do with more
eye relief if you wear spec’s; yes, they have more chromatic aberration than
the latest HD designs. But overall daytime performance is excellent.
At night, however, the chromatic
aberration isn’t a problem. Instead the high optical quality and big-eye
objectives give views that bridge the gap between binoculars and small refractors,
but with none of the softness that beset the Minox 15x58s
and with more reach (and a bigger field) than the Leica Duovid 15x50s. The optical quality is so good that these
even do well on the planets (given the limitation of 15x, obviously).
On deep sky these just show you more ...
even than Nikon’s 12x50 SEs or Swarovski’s own 12x50 ELs. Given their
performance, (relatively) small size and light weight, and the fact that they
are fully fog-proof, these make a great astronomy binocular, particularly if
you like hunting down fainter members of Messier’s list.
The Swarovski 15x56 SLCs are highly
recommended for hand-held astronomy binoculars and should be great for their
intended hunting and spotting market too. However, check you can live with
their weight and shakes (and the tightish eye relief)
before you buy.
