Fujinon 7x50 FMTR-SX
Review
7x50 was once the recommended size for astronomy and many
still prefer it for the richest of fields and a steady view. So which 7x50 is
best then? Many would answer it’s these, Fujinon’s FMTR-SXs.
But there’s a problem. These are a massive and heavy
binocular for a ‘mere’ 7x50. Mil-spec they may be, but how do they handle for
someone who can’t drop-and-gimme-fifty? I bought a pair to find out ...
At A Glance
|
Magnification |
7x |
|
Objective Size |
50mm |
|
Eye Relief |
18mm measured from eye cup |
|
Actual Field of View |
7.5° |
|
Apparent field of view |
~50° |
|
Close focus |
~~5m |
|
Transmissivity |
95% |
|
Length |
195mm |
|
Weight |
1560g measured |
Data from Fujinon/Me.
What’s in the Box?
The box on these was a bit tatty
and an older example, but typical of Fujinon packaging:
Design and Build
These Fujinon 7x50 FMTR-SXs are one of a range of large,
tough porro-prism binoculars, made with the best materials and processes. They
were introduced in the late 1980s and remain in production at the time of
writing.
There are various different models that look similar but have
different acronyms, so what do all those letters mean anyway?
F – field flattener; MT – marine tested; R- rubber armoured,
C – compass; SX – special coatings.
This pair has everything except the compass. Other models
skip the field flattener to reduce the price, or the rubber armour to reduce
weight ... a bit.
For some years now (2021) a model with updated coatings has
replaced this older version, it’s imaginatively called the ‘SX2’.
As an aside, it’s worth pointing
out how expensive these are meant to be. Often deeply discounted in the US (and
not widely available in Europe), Japanese optics shops like Kyoei show you the
truth – the FMT-SX series’ list price is the highest of any similar porro-prism
binocular, higher than Nikon’s Prostars, for example. My guess is that proper Mil-spec doesn’t come cheap.
Two very different 7x binoculars from
the 1990s: Zeiss Dialyt 7x42 and Fuji 7x50 FMTR-SX.
Body
These binoculars are U.S. Mil-spec: they don’t just look
tough, they really are, likely much more so than a pair of Alpha roofs. They
seem much more like a piece of ruggedised military equipment than a consumer
product.
The manual explains in detail what this means: a heavy
aluminium body with thick, ridged rubber armour, including built-in objective
covers on replaceable rubber sleeves. They were built to withstand extremes of
temperature, humidity, shock and vibration. They apparently include an internal
desiccant, as well as being nitrogen purged and fully waterproof. Everything
seems oversized and robust, inside as well out.
That toughness means these are heavy at 1.56 Kg. But
actually, that isn’t so very heavy compared with other 50mm binoculars, many of
which run to 1.2 Kg or more. Big for a 7x50 they certainly are, though.
Marketing images manage to make them look quite refined, but
these ‘R’ models are not that: the armour is thick, rubbery, with obvious seams
and quite a rough moulded finish. Who cares what they look like when you’re on
patrol? Too good for squaddies, maybe; but if Nikon’s Prostars
are a naval commander’s bino’s, these are a tank commander’s.
Focuser
These
have individual eyepiece focusing. In other words, you focus by just twisting
each eyepiece separately, with a scale to help. It’s a basic mechanism, but the
action is smooth and precise, likely very robust and resistant to heavy use. These
have huge depth of field, so I’ve learned three focuser settings and just dial ‘em in as needed.
Close
focus really isn’t - further than my tape measure, at very roughly 5m. ‘Forget
butterflies, boy - you’re in the army now.’
Optics - Prisms
These are a standard porro prism binocular. As such they have
no phase coatings or dielectric mirrors ‘cos they don’t need them! Those prisms
appear to be held secure with heavy metal frames, not cemented as they often
are.
Optics - Objectives
If the prisms are standard, so are the objectives: just
doublets, although they appear to have a complicated cell to hold everything
super solidly aligned.
I have no reason to believe they use special glasses,
although the front crown element is a quality glass with low laser scatter. The
lenses are quite thick and curvature strong, suggesting a shortish focal ratio.
Fuji’s SX range all feature the best coatings achievable at
the time. The manual goes into detail:
“The exclusive EBC process vaporises zirconium oxide and
applies it to every surface – uniformly in ultra-thin layers – at temperatures
over 270 °C as a beam of electrons inside a vacuum chamber.”
As I understand it, the electron beam evaporates the
Zirconium oxide in very controlled amounts, which then condenses to form the
coating in multiple thin layers.
In practice those ‘SX’ coatings are good, but not up to the
very latest standards on this 1990s pair. Still, they give a very high 95% overall
transmission with a very flat curve that remains above 90% across the whole
visible spectrum according to the graph in the manual.
As noted above, a newer version with even better coatings,
the SX2, has replaced this one and presumably now vies with Swarovski’s Habichts (with 96% transmission) for the highest
transmission figure of them all.
The barrels have no knife-edge baffles to come loose, they’re
just machined with ridges along their whole length. The objectives are held in
by two concentric lock rings, with the inner ring ridge-baffled to help prevent
flare.
Look past those green coatings to see the heavy-duty prism
straps, but also the lack of baffles.
Coatings better than a contemporary pair of Zeiss Dialyt ClassiCs.
Optics - Eyepieces
At 26mm diameter, those eye lenses are huge. They’re deeply
recessed within the eye cups, for mil-spec protection I assume. With many
bino’s that would be a recipe for poor eye relief, but not here because Fuji
claim an exceptional 23mm (from that eye lens no doubt).
With some binoculars, accurately measuring eye relief (which
can vary a lot from the claimed figure) is hard, but here the big defined and
bright exit pupil makes it easy. Whatever Fuji claims, from the lip of the
folded rubber eye cup, it’s 18mm – just right to view the whole field with my
glasses on.
Lots of eye relief very often goes with spherical aberration
of the exit pupil that causes blackouts’ as you move your eyes around. However,
these eyepieces don’t suffer from this aberration to a noticeable degree.
Talking of the eye cups, although they are the fold down
variety I don’t like, they are some of the easiest to fold I’ve encountered and
when folded they form a good lip to rest your specs’ lenses against.
Foldable eye cuos
are thicker, easier to fold than most.
Huge eye lenses
get those SX EBC coatings too.
Accessories
The box has no space for a case and so I’ve no reason to
think they shipped with one, though later versions do.
Fuji call it their ‘fashion’ strap, which seems incongruous
on what is basically a military binocular. The strap is broad and has a wide
foam pad with a sparkly green finish that makes it reflective in the dark but
looks a bit 1980s prom’ dress by day.
The eyepiece cap is huge and carries a warning about cleaning
off salt water. The objectives are closed by rubber manhole covers on removable
rubber sleeves separate from the armour - much more protective than the usual
band-on caps. All part of that mil-spec vibe. Preppers would love these.
In Use – Daytime
Ergonomics and Handling
These are huge and heavy, we know that. In practice, though,
they are surprisingly easy to handle with grippy, comfortable armour that’s
nice and warm in cold weather. They kind of sit on your palms and it’s a very stable
hold for me.
The real-world eye relief of 18mm, free from blackouts as it
is, gives superb comfort with glasses. This is one area where these beat the
other contender for the best-7x50 crown, Nikon’s Prostars.
More on the huge depth of field below, but here suffice to
note it often makes focussing unnecessary. I usually just grab these around the
objectives and view. So those individual-focusing eyepieces aren’t the problem
I expected. I have a setting for astronomy, a setting for the garden and a
third for everything in between ... that’s it. If you do need to re-focus, the
action is quite smooth and very precise.
Despite the weight, handling is very comfortable overall, but
in a very different way from a modern birding bino’. I kinda
feel like a tank commander every time I heft them.
The View
Like other big 7x50s (Nikon’s Prostars
come to mind), there’s a sense of anti-climax when you put your eye up to those
huge eye lenses. These are a big binocular, but the field seems small – low
powered and narrow. Get over that and you start to realise the view is very,
very good indeed.
The most obvious feature of the view is depth of field – it’s
massive. Leave the eyepieces set to ‘0’ and everything from about 10m out to
infinity is in perfect, cut-glass-sharp focus.
Unexpectedly, this makes the big Fujis the very best for
following birds on the wing and for nature viewing. No, really. High resolution and low false colour help.
But the real killer-app is that huge depth of
field which means that you never have to re-focus; for flying birds or running deer,
that’s a major advantage (for a military bino' too, I guess).
That claimed 95% transmissivity yields supreme daytime
brightness. It’s chastening to discover that these are slightly brighter than
the latest Zeiss 8x42 SFs, one of the very brightest premium roofs. And
remember this is an early 1990s example.
Depth and brightness are outstanding, but so too is
resolution. The more I used these the more I suspected they were revealing fine
detail other bino’s don’t. There’s a sense of so much fine detail that the
magnification isn’t enough to show it all. Combined with the absolute clarity, it’s
amazing how far you can ID tiny birds with such a low power.
Flat field?
Despite
the F-for-field-flattener in the name, these Fuji 7x50s don’t have a completely
flat field. Compared to a typical 1990s binocular – a Zeiss Dialyt
or Leica Trinovid – the field is indeed flat and well-corrected, but it’s not
perfectly sharp edge-to-edge.
During
the day, that means the last 10% or so is slightly compressed and unsharp,
though the field stop is completely usable.
View
looks almost flat to the edge, but there is some astigmatism, esp. in the last
10%.
Chromatic Aberration
Despite
large doublet achromat lenses, these only suffer from modest false colour.
There’s a trace when panning through silhouetted branches, or viewing my local
crows on the wing or in the tree-tops, but otherwise it’s never that apparent.
Overall level is about the same as mid-price modern HD roofs.
In Use – Dusk
Dusk brightness is exceptional, even though I’m likely able
to use just 6mm of the Fujis’ 7mm exit pupil. I’m able to look for Mr Badger in
the understory of the copse across the field, when a pair of super-premium
8x32s have given up already.
I did get some veiling flare under a clear and bright dusk
sky, an instance of where these underperform the very best Alpha birding
binoculars.
In Use – Observing the Night Sky
I noted that these don’t have fully modern coatings and consequently
a very bright security light generated a few dimmish ghosts. I got some veiling
flare when viewing around it too. Unlike most roofs, though, the light produced
no prism spikes or other artefacts in field, just a very clean and dazzling
image.
Dimmer stars are scattered as perfect pinpoints, but the
brightest show a little flare like most bino’s.
The F-for-flattener in FMTR-SX left me surprised that it doesn’t,
at least not perfectly. Some astigmatism and curvature creep in from just 60%,
but it’s not bad until near the edge. My usual test of putting the three belt
stars and the sword region of Orion into the field left the outer stars –
Mintaka on the right in the belt and Nair Al Saif at
the bottom of the sword - mildly distorted.
The Moon
The big
Fujis revealed a hard, sharp little world full of detail. There was no false
colour at all and minimal flare. Just after first quarter, lots of craters were
visible, despite the low power: Clavius, Tycho, Copernicus just coming into the
light, Plato in the north...
Few
roofs deliver a Moon quite this sharp and perfect. The only mark-downs were one
dim ghost and some veiling flare viewing around the Moon.
Mars
No disk
at this magnification, but Mars threw up no nasty ghosts or flare or spikes as bright
planets can.
Deep Sky
Even
though I likely can’t use the whole 7mm exit pupil, these are clearly brighter
and go deeper than my smaller binoculars. That means lots of stars and
brighter, easier to find DSOs than you expect – under dark skies, at least.
One
interesting feature was how vivid these render star colours. Betelgeuse was a
much more brilliant orange than through most bino’s, ditto Mars. The Garnet
Star was an especially rich amber, whereas through a pair of 7x42s I was
testing it barely showed gold. La Superba was the same. Despite the low power,
Albireo split nicely into its orange and flame-blue components.
The
outstanding resolution and contrast meant Orion’s belt was a mass of tiny
points of light, even in Moonlight. I was surprised at how many smaller or
dimmer DSOs I could pick out, including (after some effort) the Crab Nebula in
Taurus and the Whirlpool Galaxy in Ursa Major.
In
truth, though, 7x50s are more about sweeping the Milky Way for clusters. I had
great views of M35-M38 in Auriga, which stood out from the background brighter
and more defined than through most low power bino’s. Sweeping the area around
the Double Cluster in Perseus, I found lots of other clusters, including NGC
457 (the the Owl Cluster) and NGC 663 off Ruchbah in
Cassiopeia; I easily found the nebulosity in the nearby Heart and Soul Nebulae
too.
For sweeping star fields, the FMTR-SXs are among the best 7x
binoculars at any price.
7x50 FMTR-SX vs Nikon
7x50 IF SP WP ‘Prostar’
Both come from a
tradition of large Japanese porro-prism 7x50s, with similar specs and build, from
various makers including (at one time) Takahashi and Canon. These are the only
two that survive as of 2021.
Both feature full
waterproofing, individual focus and very rugged construction.
The Nikons have been
tweaked (from their more generic Tropical model) especially for astronomy with ‘special
purpose’ glass and a very flat field edge-to-edge. The Fujis have a slightly
wider (but less perfectly corrected) field, more eye relief and full US Mil-spec
construction (note the heavier-duty bridge and eyepieces).
Wear glasses to view
(with such a low power you probably should if you have much astigmatism) or
need their super-tough construction? Buy the Fujis. Otherwise, the Nikons.
Summary
I believe that when you join the
Special Forces you get to choose your own gear. I have no view on Armalite vs
SIG Sauer, but for binoculars I can recommend these Fujinon 7x50s. Tough,
dependable, with a super-sharp ultra-bright view.
And everything in your Bergan’s heavy, anyway, right?
Get past the size and weight and
you find top-level optical refinement. The field is rather narrow and the edge
correction not quite as good as the ‘F’ might suggest, not as good as
Nikon’s Prostars’. Otherwise, these are the best of the
best: supreme (on-axis) resolution and brightness, low false colour and huge
depth of field.
Outstanding focus snap (esp. for a
7x50) and that depth of field mean the individual focusing isn’t the pain you
expect. Comfort, in the hold and at the eyepiece, is faultless.
For astronomy, these deliver very
bright and crisp star fields, even to my older eyes. I’d generally prefer a wide-field 8x binocular for
sweeping the Milky Way, but if you’re under 40 these will give
unrivalled rich field views, with the most intensely pinpoint and strongly
coloured stars.
The Fujis’ only Achilles’ heal is stray light. The insides aren’t as well baffled as
some and you get momentary flare working around streetlights or the Moon, or at
dusk, as light from off-axis strikes a lens or prism or barrel internal.
If you just want a low power bino’ for its steady bright view,
then a modern 7x42 might be a better bet. But if you’re young enough to use the
full 7mm exit pupil and you’re not bothered by their weight, Fuji’s 7x50 FMTR-SXs
have supreme optical quality and ruggedness with great comfort too.
