Zeiss Conquest 10x56 HD Review

Zeiss’ latest Conquest HD binoculars appear to offer great value and a very high spec’, especially in the big-eye versions. In this review, I find out if those class-leading numbers pan out on test, or if Zeiss has had to cut corners to meet the keen price.

Big-eye (large aperture) binoculars in higher powers are made for the hunter, but they’re ideal for hand-held astronomy too. A few years ago, premium examples were thin on the ground. Now more manufacturers are coming out with new models. The eagerly-awaited mid-range Zeiss Conquest HD are a good example of a once marginal model that has been re-booted with HD optics and a complete range of sizes from 8x32 all the way to 15x56. Here I take a look at the Zeiss Conquest 10x56 – a size perfect for astronomy.

Zeiss’ new Conquest HD models are relatively inexpensive, so they must be made in China, or Hungary (like the Victory 8x20s) right? Wrong: they’re made in Germany. Alright then, given that low price point there must be some obvious compromise: narrow field, tight eye relief? Again, wrong. On paper, at least, the spec’ of these looks class-leading in every way. Surely there must be a catch? Let’s see …

At A Glance

Magnification	10x
Objective Size	56mm
Eye Relief	18mm
Actual Field of View	6.7 degrees
Apparent field of view	66 degrees
Close focus	3.5m
Transmissivity	90%+
Length	210mm
Weight	1275g

Data from Zeiss

What’s in the Box?

Design and Build

Zeiss have brought this new HD version of the Conquest model bang up-to-date. They have those all-important HD lenses to reduce false colour fringing, but they also get a new body and armour that has the Zeiss house look. The eyepieces are different too – a wide field design with massive eye lenses like the best premium models.

As we will see, there are a few specific areas where costs have been cut, but basic build quality – mechanical and optical – is typically Zeiss and not compromised at all.

Internal construction looks good too; and rugged. But it appears slightly more agricultural, with a few more rough surfaces and obvious grease, than a pair of Zeiss Victorys.

Body and Ergonomics

First impressions of the Zeiss Conquest 10x56 HD are that they are very similar to the much more expensive 10x54 Victory HTs I tested last year. Everything about them, from the tapering shape to the thick two-texture armour looks similar.

In fact, these are quite a bit longer (210mm vs 193mm) and heavier (1275g VS 1050g) than the HTs. They are quite a large binocular. They’re larger than Swarovski’s 56mm SLC HDs too.

They also have a more conventional design with an armoured hinge and the focuser at the back, rather than the double-link bridge and huge central focuser on the HTs. They have gone for the ‘normal’ 56mm objective too, rather than the cut-down 54mm objectives of the HT which allow that model to look and weigh more like a 10x50.

The design and size of these 10x56 Conquests is very similar to the older Swarovski SLC (not the newer one compared in this review, which is smaller).

Zeiss don’t sculpt the back for thumb cut-outs, unlike the SLCs which now get a two-stage cut-out that really makes for a snug fit in the hand.

Zeiss Conquest 10x56 HD and Swarovski 10x56 SLC HD

Focuser

The focuser is simply excellent, smooth and precise and quite light in feel. It does have a small vague spot that the very best don’t, but you won’t notice this in use. The focuser is fast too, really fast: less than a turn from 3m to infinity, just like a premium birding bino’. Curiously, it’s faster than the HT’s focuser.

Unfortunately, the dioptre adjustment is less good. It’s in the old-fashioned place as a ring under the right ocular, but it’s stiff and has no click-stop positions: vastly inferior to the typical Swarovski (and earlier Victory FL) mechanisms, but in truth not much worse than the Victory HTs’.

Dioptre adjustment is a conventional ring underneath the right eyepiece

Optics - Prisms

Like the 10x54 Victory HTs (and the new Swarovski SLC HDs) these new Conquests get the Abbe-König prisms that Zeiss pioneered and that give a slimmer profile and more light throughput because they don’t need lossy mirror coatings, unlike the Schmidt-Pechan prisms found in most roof-prism binoculars. In this case, the transmission quoted is 90%, which is less than the HTs (which are quoted at 95%) and less than the SLC HDs too. As we will see, though, these are a very bright binocular, just like the Zeiss FLs and Dialyts before them.

Interestingly, it’s only the 56mm Conquest HDs that get Abbe-König prisms – the 42mm and 32mm models have conventional roof prisms.

Optics - Objectives

Zeiss claim to use ED (i.e. high-fluoride) glass in these latest Conquests – hence the ‘HD’ label - and as we will see they have low (but not zero) chromatic aberration levels.

There is now some confusion about ‘HD’ in binoculars. Early models boasting this feature, like the Zeiss FLs and the original Leica Ultravid HDs, had a single element of high-fluoride glass that cut false colour fringing to low levels. The very latest premium binoculars seem to have stepped chromatic aberration down another notch to almost zero by employing extra high-fluoride glass elements or better glass types (high-fluoride glass comes in different qualities).

The Zeiss Victory HTs use a complex four element design with two ED elements. Which system the Conquests use isn’t stated by Zeiss, but from the level of false colour I am guessing it’s just one ED element per objective.

The Conquests’ objectives are well-recessed with micro-ridged lens rings and two large knife edge internal baffles for stray-light suppression.

The T* coatings on these Zeiss Conquests are absolutely top quality - as good as, or better than, the latest Swarovski coatings. They have a slightly pinkish hue that gives a cool colour balance. Zeiss has always been proud of the excellence of its T* coatings and these show why. They have the latest dirt-shedding “LotuTec” feature as well.

Objectives are well baffled with ridges and knife-edges

Zeiss T* coatings look every bit the equal of Swarovskis SLCs’

Optics - Eyepieces

The eyepieces have very large (25mm) eye lenses, like you find on wide-field telescope eyepieces. They also yield a very large (for binoculars) apparent field of 66 degrees that is getting up into wide-angle territory, again like an astro’-eyepiece. Unlike a modern astro’-eyepiece, however, the field quality drops off a lot towards the edge, so the usable field isn’t quite as large as it sounds.

Eye relief is claimed to be 18mm, 2mm more than the 10x54 HTs – in theory. Perhaps from the eye lens that’s true. But the problem is the very deep ridges running around the rim of the eye cups that mean in practice it’s more like 16mm measured from the rim of the cups. So, real-world eye relief is much less than Swarovski’s 10x56 SLC HDs’, less in practice than the HTs’ too; I can’t see the whole field with my specs on.

Blackouts (spherical aberration of the exit pupil) aren’t a significant issue, which is good news.

The adjustable eye-cups have only two positions (many premium examples have three). Compared to the best they are soft-feeling and the action is stiff and vague. On my sample the left one was looser than the right too. This is one area where a bit of cost-cutting is evident – they are much poorer quality than the Victory HTs’.

The left hand eye cup was a bit loose and wobbly, as you can see here.

Accessories

The Conquests come with the usual functional-but-no-more Zeiss cordura case, rubber eyepiece caps and push-in rubber objective caps that attach via a little lanyard.

Note: the 15x56 Conquests get a tripod adapter; this 10x56 model does not.

In Use – Daytime

Ergonomics and Handling

Handling is perfectly good, but I prefer the thumb cut-outs on the Swarovski SLCs. I prefer the look and feel of Swarovski’s armour too. These need to be held around the barrels, making the focuser a long way off.

These Conquest 10x56s are a larger, heavier binocular than the 10x54 HTs and they feel it. The weight of 1275g has passed a threshold where I couldn’t wear them all day, probably not even for static birding, never mind walking. They also look much more bulky hanging around your neck: you could never mistake these for a birding bino’ like you might with the compact HTs. They also feel heavier and bulkier than the SLC HDs.

One area where these Conquests are better than the Swarovski SLCs is the objective caps. The Zeiss caps push deep into the objectives and stay put; the Swarovskis constantly come loose. The Zeiss caps attach by little lanyards, an alternative to the Swarovski band-on system.

The focuser is excellent, with a good feel and perfect weighting under a gloved finger. It is also very smooth, light and fast. I don’t like the dioptre mechanism, but the snappy optics means it’s not too hard to adjust in practice and certainly won’t shift accidentally (it is very stiff).

The eye cups have a pretty nasty action on my pair – rough and inexact, they feel different on each barrel. They’re not a patch on the Swarovski SLCs’, or the Victory HTs’.

The effective lack of eye relief due to those ridged eye cups makes these much less comfortable than Swarovski’s SLCs and less comfortable than the HTs too. The very wide field actually makes you believe you’re seeing all of it with glasses; but take them off and you realise you’re not.

If you wear specs, try these before you buy: the real eye relief may not be sufficient for you.

Zeiss Conquest 10x56 HDs are quite a big binocular to hold.

No one is going to mistake the 56mm Conquests for a birding binocular, the way they might with the 10x54 HTs.

The View

The view is very good indeed: sharp and clear, with none of the softness I have seen in big-eye binoculars. Colours are neutrally, perhaps rather coolly rendered, with no nasty yellowish tints. Resolution in the centre-field is excellent; rather less so off-axis (see comments below).

Focus snap is an absolutely precise point in both barrels – a sure sign of top-quality optics.

The view is both very bright and spectacularly wide, something immediately noticeable that I really like.

I should point out again here that daytime brightness is not due to the big 56mm lenses, because the eye’s contracted pupil effectively stops them down to be something like 10x30s. Rather, daytime brightness is controlled by the transmissivity of the lenses and prisms.

This is one area where these Conquests lose out to the premium Victory HTs, on paper at least. They supposedly transmit 5% less light than the HTs, despite having Abbe-König prisms. Even so, brightness is really excellent for a big-eye binocular – much better than Swarovski’s old (pre-HD) SLCs and similar to the new SLCs which also benefit from Abbe-König prisms. Compared to the competition, these are one of the brightest binoculars, something my daughter – not a binocular expert - immediately noticed.

The daytime view is really excellent – better than most and close to the (more expensive) class leaders. Once again there isn’t the usual penalty for a big-eye design: these give a view much like a fine 10x42 birding binocular.

Flat field?

In a word, no. That very wide field comes at a price and as usual with Zeiss, it’s off-axis aberrations - field curvature and astigmatism - which increase towards the field edge, where the view is distorted in a way it isn’t with the SLC HDs. This doesn’t matter as much as it might, because the field is also wider than almost any other modern 10x binocular I can think of.

You can see the off-axis curvature in this snap.

Chromatic Aberration

Chromatic aberration is well controlled in the centre of the field – similar to most other premium HD models, but not quite as good as Swarovski’s class-leading SLC HDs and perhaps just a bit more than the Victory HTs too. Chromatic aberration increases markedly towards the edge, though.

A pair of black rooks against a bright sky show a noticeable purple and green fringe that isn’t there through the Swarovskis. Nonetheless, I can enjoy all the plumage detail of a pair of pigeons roosting in high branches without false colour ruining the view.

In Use – Dusk

The big lenses and bright optics mean dusk views with these are as good as you’ll get. They really penetrate into deep dusk gloom and have that light-intensifier effect, even in full night. Higher magnifications get a higher ‘twilight factor’ rating, but for me this 10x56 size is the best you can get for dusk work.

At about ten pm on a dark winter night, I watched a badger snuffling about in the field opposite, even though the only illumination was a dim glow from some Christmas fairy lights a few hundred metres away. The fields looked completely dark to the naked eye. They should issue these to the SAS.

In Use – The Night Sky

But what about for astronomy? In fact, if you do the maths, these turn out to transmit almost exactly the same amount of light to your eyes as the HTs do (very slightly more in fact) because of their larger objectives: in theory, they should be every bit as good on the night sky as their expensive sibling.

I noted the off-axis aberrations during the day, but they are more pronounced at night. Stars are nicely pin-point centre field with strong colours, but from about 60% field width there is some field curvature and stars become obviously astigmatic and slightly comatic too – aberrations which can’t be focussed away.

The field is so wide that it’s possible to get Castor and Pollux in the field with room to spare, but doing so both stars are at about 80% field width and both are comet shaped. The effect also spoils the view of Orion, where the whole sword and belt easily fit in the field, but the outlying stars are strongly distorted. By the field stop, astigmatism has taken over and stars are almost linear.

The shear width of the field means off-axis aberrations aren’t the problem they might be – you can still get a great view of the Pleaides with all the stars in the central sweet spot, for example – but it’s not ideal for astronomy.

Stray light protection is good – a bright light (or the Moon) just outside the field produces no veiling flare and a full Moon doesn’t cause ghosts. However, a bright security light in the field produces a trace of ghosting and a few faint, long flare spikes. This is an area where the Conquests fall short of premium models (including Zeiss Victorys and Swarovski SLC HDs) which don’t produce these ghosts and spikes on the same light.

The Moon

I had a splendid view of a week-old Moon through the Conquests. The Moon was sharp and hard and full of contrast and detail, with no softness and virtually no false colour or flare.

I was easily able to make out individual craters on or near the terminator – Aristoteles in the north, Maurolycus is the south and the grouping of Theophilus, Cyrillus and Catherina on the edge of Mare Nectaris.

Later, I watched the Moon set into thin cloud behind winter branches in silhouette. The HD lenses perfectly transmitted the baleful yellowish tints of the misty Moon, the dark branches and the veil of cloud with no hint of false colour. Contrast was so good that I could still see masses of craters, even though the Moon looked washed out and featureless to the naked eye.

Later in the month, even a near-full Moon presented no problems with false colour or flare.

Venus

Venus showed just a little more flare and spiking than the very best, but still not enough to regard as a problem. False colour was well controlled on Venus too.

Jupiter

Jupiter showed as a near-perfect disk with just a hint of flare. The Galilean moons were easily picked out.

Deep Sky

The pin point star images centre field, large objectives, superb coatings and high-transmission Abbe prisms really show up on deep sky. With these binoculars you just see a lot more faint stars.

The Pleiades show a mass of fainter stars embedded among the seven sisters through these big-eye Conquests.

I got a great view of the Orion sword region with lots of nebulosity. I like that extra wide field for context, even if the stars are distorted.

The chain of open clusters in Auriga looked good, with the wide field fitting several in at one go and lots of stars delivered by the big objectives and good transmission. Again star colours were nicely intense.

On a dark night finding smaller DSOs is easy, but these can’t pick them out of Moonlit or light-polluted skies the way 15x56s can.

Overall performance on the night sky is very good, even though astigmatism and field curvature smear stars beyond 60-70% field width in a way the best don’t.

Astronomy with the Conquest 10x56s

Zeiss Conquest 10x56 HD vs Swarovski 10x56 SLC HD

I’ve made a lot of passing comparisons with Swarovski’s 10x56 SLC HDs which I tested alongside these. They are an obvious competitor, although more expensive. A summary of their relative merits follows:

· The SLCs are about 100g lighter.

· The SLCs are about 1cm shorter in length.

· The Conquests lack thumb cutouts but are still comfortable to hold.

· The SLCs have a slightly brighter view, but the Conquests are still a very bright binocular.

· The SLCs have less chromatic aberration (i.e. essentially none) centre field and much less towards the field stop.

· The Conquests have a visibly wider field, but aberrations – field curvature, coma, astigmatism and false colour too – increase more off-axis than the SLCs’, so usable field is no more, perhaps less.

· The SLCs are subjectively slightly sharper and higher in resolution.

· The SLCs have much more (4-5mm) eye relief in practice and so are better for specs wearers.

· The Conquests’ focuser is just as smooth and accurate, but has a touch of free-play the SLC’s doesn’t.

· The Conquests produce faint flare spikes and ghosts from bright artificial lights in-field that the Swaros don’t, but not enough to spoil the view.

· The Conquests’ dioptre adjustment is markedly inferior.

· The Conquests’ eye cups are rougher in action and poorer quality.

· The Conquests’ armour is smoother and less pleasant to my hands, much easier to mark.

· The Swarovskis feel like a slightly higher quality product (but this is subjective).

· The Conquests are currently about 40% cheaper with discounts.

Overall, I prefer the Swarovski 10x56 SLC HDs, but apart from the Conquests’ off-axis aberrations, the differences are fairly subtle. Whether the Swarovskis are worth the extra cost is up to you.

Summary

The Zeiss Conquest 10x56 HDs are great binoculars with a really wonderful view. I really like them. But they are not ‘almost perfect’ the way the more costly Swarovski 10x56 SLC HDs are. Let’s break that management summary down.

Optical quality is top notch with absolutely snappy focus. Chromatic aberration is well controlled, but still present and worse off-axis. The focuser is precise and smooth, but with a touch of play the best don’t have. Build quality is generally good. The daytime view is sharp, detailed and both spectacularly bright and wide. In some ways both the view and the focuser exceed my expectations.

And yet … The view overall isn’t quite as good as the Swarovski 10x56 SLC HDs’: a bit more curved with a little more false colour; just a touch less pleasing overall. But I’m being very picky here – by general standards, the view is excellent, something you’ll really notice the first time you look through them.

There are downsides, though. In theory, these have more eye relief than the Victory HTs; in practice they have less – not quite enough for my glasses. The field width is like that too. On paper they have the widest of fields, but it drops off at the edge more than the Swarovskis’ and the last 20% or so isn’t really usable apart from giving ‘context’. There are a few build niggles, as well: the stiff dioptre mechanism, the rough action of the eye-cups, the lack of thumb indents and the less pleasant feel of the armour.

So is there a catch after all, then? Absolutely not. These are an excellent pair of binoculars that perform superbly for their modest price in the most important areas: optics and focuser. But the winning numbers turn out not to be quite what they seem on paper and there are a few areas where these fall below the quality of the very best.

Nonetheless if you want a premium pair of big-eye binoculars with a really great view for a sensible price, you’ve just found them. In many ways, I prefer the 10x56 Conquests to the 10x54 HTs because they are almost as good but much cheaper.

If you don’t want to spend the extra 40% for Swarovski’s 10x56 SLC HDs, these are highly recommended. They are unquestionably great value for money and give a wonderful view, day or night.