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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 itís these, Fujinonís FMTR-SXs.

But thereís a problem. These are a massive and heavy binocular for a Ďmereí 7x50. Mil-spec they may be, but how do they handle for someone who canít 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

7.5į

Apparent field of view

~50į

Close focus

~~5m

Transmissivity

95%

Length

195mm

Weight

1560g measured

Data from Fujinon/Me.

Whatís 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 Ė field flattener; MT Ė marine tested; R- rubber armoured, C Ė compass; SX Ė 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, itís imaginatively called the ĎSX2í.

As an aside, itís 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 Ė the FMT-SX seriesí list price is the highest of any similar porro-prism binocular, higher than Nikonís Prostars, for example. My guess is that proper Mil-spec doesnít 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 donít 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 isnít 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 ĎRí 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 youíre on patrol? Too good for squaddies, maybe; but if Nikonís Prostars are a naval commanderís binoís, these are a tank commanderís.

Focuser

These have individual eyepiece focusing. In other words, you focus by just twisting each eyepiece separately, with a scale to help. Itís 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 Iíve learned three focuser settings and just dial Ďem in as needed.

Close focus really isnít - further than my tape measure, at very roughly 5m. ĎForget butterflies, boy - youíre in the army now.í

Optics - Prisms

These are a standard porro prism binocular. As such they have no phase coatings or dielectric mirrors Ďcos they donít 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.

Fujiís SX range all feature the best coatings achievable at the time.The manual goes into detail:

ďThe exclusive EBC process vaporises zirconium oxide and applies it to every surface Ė uniformly in ultra-thin layers Ė at temperatures over 270 įC as a beam of electrons inside a vacuum chamber.Ē

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 ĎSXí 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 Swarovskiís Habichts (with 96% transmission) for the highest transmission figure of them all.

The barrels have no knife-edge baffles to come loose, theyíre 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. Theyíre deeply recessed within the eye cups, for mil-spec protection I assume. With many binoís 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, itís 18mm Ė 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 blackoutsí as you move your eyes around. However, these eyepieces donít suffer from this aberration to a noticeable degree.

Talking of the eye cups, although they are the fold down variety I donít like, they are some of the easiest to fold Iíve encountered and when folded they form a good lip to rest your specsí 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 Iíve no reason to think they shipped with one, though later versions do.

Fuji call it their Ďfashioní 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 promí 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 Ė 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 thatís nice and warm in cold weather. They kind of sit on your palms and itís 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, Nikonís 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 arenít the problem I expected. I have a setting for astronomy, a setting for the garden and a third for everything in between ... thatís 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 binoí. I kinda feel like a tank commander every time I heft them.

The View

Like other big 7x50s (Nikonís Prostars come to mind), thereís 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 Ė 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 Ė itís massive. Leave the eyepieces set to Ď0í 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, thatís a major advantage (for a military bino' too, I guess).

That claimed 95% transmissivity yields supreme daytime brightness. Itís 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 binoís donít. Thereís a sense of so much fine detail that the magnification isnít enough to show it all. Combined with the absolute clarity, itís 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 donít have a completely flat field. Compared to a typical 1990s binocular Ė a Zeiss Dialyt or Leica Trinovid Ė the field is indeed flat and well-corrected, but itís 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. Thereís a trace when panning through silhouetted branches, or viewing my local crows on the wing or in the tree-tops, but otherwise itís never that apparent. Overall level is about the same as mid-price modern HD roofs.

In Use Ė Dusk

Dusk brightness is exceptional, even though Iím likely able to use just 6mm of the Fujisí 7mm exit pupil. Iím 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 Ė Observing the Night Sky

I noted that these donít 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 binoís.

The F-for-flattener in FMTR-SX left me surprised that it doesnít, at least not perfectly. Some astigmatism and curvature creep in from just 60%, but itís 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 Ė 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 canít 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 Ė 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 binoís, 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 Orionís 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 binoís. 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 ĎProstarí

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 Ďspecial purposeí 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 Berganís 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 ĎFí might suggest, not as good as Nikonís Prostarsí. 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 isnít 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. Iíd generally prefer a wide-field 8x binocular for sweeping the Milky Way, but if youíre under 40 these will give unrivalled rich field views, with the most intensely pinpoint and strongly coloured stars.

The Fujisí only Achillesí heal is stray light. The insides arenít 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 binoí for its steady bright view, then a modern 7x42 might be a better bet. But if youíre young enough to use the full 7mm exit pupil and youíre not bothered by their weight, Fujiís 7x50 FMTR-SXs have supreme optical quality and ruggedness with great comfort too.

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