Zeiss Conquest Gavia
85mm Scope Review
I recently wrote my first proper review of a spotting scope,
something I’ve been wanting to do for a while. That scope was Zeiss’ premium
Victory Harpia 85 and I was impressed: giving wonderful views by day, the Harpia
really surprised me by working for astronomy too. Meanwhile I loved its compact
size and low weight.
But the Harpia has a downside – cost. It’s an expensive
device. Worth it? Yes! But what if you don’t want to invest that much in a
scope? Just as they do in their binocular range, Zeiss have another current
offering at a more modest (though still quite high) price-point: the Gavia on
test here. How does it compare to the premium Harpia? Read on to find out...
At A Glance
|
Magnification |
30x-60x |
|
Objective Size |
85mm |
|
Eye Relief |
~13mm measured. |
|
Actual
Field of View |
33m
– 23m / 1000m |
|
Apparent field of view |
1.9° – 1.3° |
|
Close focus |
3.3m measured. |
|
Transmissivity |
88% |
|
Length |
390mm (incl. eyepiece, Sun-shade
retracted) |
|
Weight |
1460g body only, 1780g incl. eyepiece. |
Data from Zeiss/Me.
What’s in the Box?
The Gavia gets a similar box to the
Harpia, with a magnetic catch and a thick foam lining. Only the big nature
photo is different.
Design and Build
Zeiss currently have two lines of spotting scopes – Victory Harpia
and (this one) Conquest Gavia.
The Harpia comes in 95mm and 85mm apertures and is Zeiss’
premium scope, part of a range of top-end products under the ‘Victory’ label,
including their ‘SF’ birding binoculars. All Victory products are of European
manufacture, as far as I know.
The Gavia, meanwhile, is part of Zeiss’ budget-premium (?!)
Conquest range and like the Conquest binoculars it’s proudly made in Ger...
(screeching sound of needle being dragged off vinyl).
Scratch that last, because in fact, the label on the Gavia
box tells you it wasn’t made in Germany at all, but under license in Japan.
Does this matter?
In terms of the build quality, absolutely not. I couldn’t
find any evidence that the mechanical and optical fabrication quality (rather
than the optical and mechanical design) is any different from Zeiss West’s. It
looks the same. Fit and finish are the same. If not for that ‘Japan’ on the
box, I wouldn’t have known. This isn’t a re-badged generic scope: external appearance
and finish of the Gavia is pure Zeiss; the coatings are typical Zeiss T* too.
Whilst outsourced build might have vague status implications,
there are two possible real issues for you as a buyer: future
saleability and repairability. I don’t know about either, but both are
something to consider.
Labels on the similar Harpia 85 and Gavia 85 boxes betray
different origins.
Finish looks typical Zeiss and much like Harpia’s.
Body
First impressions? If I was surprised at the small size of
the Harpia, I was amazed at how small and light the Gavia 85 is, just as Zeiss
claim.
The Gavia is light because it’s made of a magnesium. I
measured just 1460g w/o the eyepiece, which is 25% (480g) less than the Harpia.
The Gavia 85 is 30mm shorter than the Harpia 85 too.
Like the Harpia, the Gavia’s
outward appearance seems a little plasticky, whilst also feeling much more like
a mass-market consumer product (a camera maybe) than most of the astro’ telescopes
I review.
Closer inspection reveals excellent fit and finish, much like
the Harpia’s, as I noted above. Like the Harpia, the armour on top is smooth, black
and slightly shiny. It’s quite thick (about 2.5mm), doesn’t attract prints or
fluff too badly and has only a faint odour of rubber. However, I did notice
that it is quite prone to nail scratches and marking.
Underneath and at the back is a textured area for grabbing
the scope to move it about. Here the armour is different to the Harpia’s, though,
with much more subtle texturing.
At the front is a sliding dew-shield/sun-shade that clicks
out with 40mm of travel to protect the lens in use. It slides fine, but with a
less refined and smooth action than the Harpia’s.
At the other end is a port with a bayonet fitting for the
eyepiece. I’ll talk more about this in the eyepiece section below.
Despite its light weight, the Gavia is nitrogen filled and
waterproof to 400 mbar, same as their binoculars.
Zeiss Victory Harpia 85 for comparison.
Focuser
The
focuser is the deeply-ribbed ring that encircles the scope at the back. The
ribbing is the same style as the Harpia’s, but the Gavia doesn’t get the
Harpia’s innovative, but for me slightly flawed, two-speed focuser. Neither is
there a zoom ring here, like the Harpia’s, because the zoom control is
conventionally located on the eyepiece.
Despite
a lack of fine focus control, the focuser’s action is close to ideal for me and
I never felt the need for one: it’s smooth but weightier than the Harpia’s so
no danger of defocusing by accident. It’s precise too and has no slop. I could
find no difference in focus position when focusing though and then backing out,
a key benefit for me as I habitually focus that way.
The
Gavia is not parfocal across its zoom range – it’s not too far off, but zooming
mostly needs a quick nudge on the focuser.
Close
focus is an outstanding feature of the Gavia – I measured just 3.3m across the
whole zoom range just as Zeiss claim, almost the same as the Harpia. It’s a
fabulous feature that allows the Gavia to function as a long-distance
microscope.
The
focuser is fast, with closest focus to infinity taking less than a single turn.
I left
the Gavia out for some hours in temperatures around freezing, to see if the
focuser and/or zoom would stiffen up. They didn’t.
Focuser is the ribbed ring.
Optics - Objectives
The fixed part of the objective appears to be an air-spaced triplet
comprising a single centre element of flint glass, sandwiched between two
crowns. Zeiss claim ‘HD’ optics, but based
on laser scatter and performance (see below) I would guess these are not the Ultra-FL glass found in the Harpia, but a cheaper ED glass of some type.
Well behind the objective proper are a focusing lens and then
a separate zoom lens assembly.
The objective’s focal length is a fixed (unlike the Harpia’s)
494mm, giving a focal ratio of F5.8. That’s similar to a fast astro’ scope
designed with wide fields and imaging in mind.
The Gavia has the usual pinkish T* coatings (a Zeiss
trademark for almost a century) which are very transparent. The coatings also
include Zeiss’ LotuTecTM water-repellent
treatment that makes it easier to wipe away fingerprints.
There are a couple of proper knife-edge baffles behind the
objective to kill stray light. The lens ring and focuser carriage have
ridge-baffles machined in for the same reason.
Look past the typical T* pink coatings to see knife-edge and
ridge baffles to control stray light.
Optics – Eyepiece
The
Gavia comes with a zoom eyepiece that varies between ~8mm and 16mm in focal
length. The eyepiece is quite large, but not heavy.
The
eyepiece secures to the scope via a twist-lock bayonet fitting with solid metal
blades that holds it very securely. Unlike the Harpia, there is a locking ring
on the body that acts as belt-and-braces to secure the eyepiece in addition to
the bayonet.
The zoom
magnification range of 30x-60x compares with 22-65x on the Harpia 85. This
doesn’t sound too different, but it feels much more so in practice, because
unlike the Harpia, apparent field of view varies with magnification, a key difference.
Zoom
eyepieces are often prone to a narrow apparent field at low power and this one
is no different: the apparent field widens as you zoom in, so that the field of view at 1000m only varies
between 33m at 30x and 23m at 60x. The Gavia’s
maximum true field of 1.9° at 30x is
quite constricted (much more so than its barrel size could theoretically
permit).
If you
take Tele Vue’s advice about choosing eyepieces based on field width not
magnification, the Gavia’s zoom is consequently less
useful than the magnification range might suggest: magnification varies by a factor
of two, but the field of view by just 30%.
Eye
relief measures roughly 15mm from the rim of the eye cup and seems to maintain
it across the zoom range, but I can only see the whole field at the 30x zoom
setting. For those who view without glasses, the eye cup twists out and extends
with two out positions. Unlike some Zeiss eye cups the twist-and-click action
is smooth and positive.
Eyepiece
has twist-out cup with two positions to accommodate the ~15mm eye relief.
Mounting
The Gavia has a
built-in mounting ring, in which the scope can be rotated having loosened a
lock knob on the right side. It rotates smoothly, with click-stops and a
refined weighty feel.
Attached to the ring is a mounting shoe that can function as
a dovetail, but also has a standard ¼ - 20 thread for tripod mounting as an
insert in a 3/8 thread.
I mounted the Gavia on a light Berlebach
ash tripod with a matching head that works perfectly and looks good in a
domestic setting, too.
For serious field use, you would choose a carbon tripod and a
heavier scope-specific head.
The Gavia 85 is smart enough for a domestic setting.
Accessories
The Gavia comes with a push-in objective cap that I found
quite stiff and tricky to remove. The eyepiece comes with a cap on a lanyard
and there are caps for its bayonetted end and the open end of the scope too.
No case is provided, but you can buy a quality stay-on case
as an accessory.
Another useful accessory that the Harpia doesn’t get is an
adapter to allow the fitment of 1.25” astro’-fit eyepieces, of which there is
of course a huge range available. Experiments with Tele Vue eyepieces, Nagler
and Panoptic, suggest these might be an interesting alternative to the standard
zoom.
A 19mm Panoptic, an eyepiece neither particularly large nor expensive,
gave a really superb view at 26x, a huge improvement over the 30x setting of the
standard zoom eyepiece.
This also offers the possibility of increasing the range of magnification
and field of view: a 32mm Plossl giving just 15x, and a 5mm Nagler giving 99x,
both focused up nice and sharp (though the high power gave a lot of false
colour). Meanwhile, the 32mm Plossl gives a much wider field of 3.1° than the standard eyepiece’s 1.9°.
In Use – Daytime
Ergonomics
Eyepiece comfort is good with no troublesome blackouts at low
power, with or without specs. Even at 60x, blackouts are minor.
Like the Harpia, eye relief is sufficient that I can see all of
the field with specs on, but only if I really push my specs into the
eye cup, otherwise I lose a lot of the field, especially at 60x where the apparent field
is wider.
As I
mentioned before, the Gavia is close to parfocal across the zoom range but
annoyingly not quite. Still, re-focusing is easy because the focuser action is
very positive and precise.
The Gavia is so compact and light, it’s not an issue to just
pick it up and carry it on a tripod – even easier than the Harpia.
The View
Given the Gavia’s lower price and
outsourced manufacture I was expecting a lacklustre view, but not so. The view
is really very good: sharp, full of detail, and bright too. There is no
softness, even at high power, and focus snap is always an absolute point – a
sign of great optics.
Views of waders out on the bay sands are pin-sharp, as are
the ripples and waves of the incoming tide. Across the bay, the woods and
villages are picked out with perfect detail and contrast.
Nearer to home, I can enjoy close-up views of the spring
flowers poking up through last year’s leaves in the under-storey of my local
copse, where light levels and contrast are low.
The elephant in the room with the Gavia is the field of view.
As I pointed out above, it only narrows by 30% as you zoom in, so that lower
powers deliver steadiness and depth of field, rather than the much broader view
you expect. I
found myself really wanting a lower-power/wider field zoom setting in the
Gavia, much more so than with the Harpia.
1x zoom - 30x magnification: sharp but narrow.
2x zoom – 60x magnification: sharp and detailed on-axis, but
depth of field is very shallow.
Flat field?
As I
noted above, the field appears sharp edge-to-edge by day, even at minimum focus
distance and maximum zoom, confirmed by viewing a meter rule 3.5m away. Only
when viewing stars do you realise that there is a little curvature and
astigmatism towards the edge.
There is
also a bit of pin cushion distortion, probably to allow comfortable panning.
Even so, panning does create some ‘rolling ball’ effect.
Chromatic Aberration
My usual
way of assessing false colour is viewing silhouetted branches at high power.
The Harpia 85 really surprised me by passing this test almost to perfection; the
Gavia 85 not so much.
Despite
a triplet objective and ‘HD optics’, the Gavia shows some purple-and-green
fringing from the objective around silhouetted branches when focusing through
at the maximum zoom setting of 60x. There is minor in-focus false colour too.
This would be typical of an astronomical telescope with an ED doublet
objective, of similar aperture and focal ratio, at this magnification.
Even at the
lowest power of 30x, there is a trace of false colour and more off-axis from
the eyepiece. None of this is ruinous, but in birding or nature viewing in
high-contrast situations – silhouette, snow, bright water etc – you may notice
it.
In Use – Dusk
The Gavia continues to give good views in low light, but only
at lower magnifications. For high-power viewing in twilight
you might need to consider a larger aperture.
In Use – Observing the Night Sky
General Observing Notes
One of my main goals in testing the Gavia was to see how it
performs for astronomy, so I’ll spend some time going into detail. Just skip this
section if you’re not interested!
For a
proper star test 60x is a bit low powered and star-testing a scope intended for
terrestrial use is arguably unfair anyway. Nonetheless, the star test looked
good, with nice rings one side and slightly fainter ones the other. I noticed only
minor false colour in the star test, even on Sirius.
Even
on-axis, The Gavia shows a little astigmatism on stars, in a way the Harpia
didn’t – a delivery more typical of binoculars. Minute crosses they may be, but
stars still appear basically pinpoint on casual inspection. And astigmatism
only increases a little towards the field edge.
By day,
the Gavia’s field appears sharp-to-the-edge, but at
night stars do become progressively a little blurred off axis at 30x, but it’s
mostly curvature and can be focused away. Sensibly, at the highest powers the
field is almost flat.
One unexpected issue was that the maximum field of just 1.9° at 30x made finding fainter targets very challenging without
a finder, more so than with binoculars that share your naked-eye line of sight.
I often got lost trying to find DSOs among the stars, where I didn’t so much
with the Harpia.
The limited zoom range made it a less useful feature than the
Harpia’s for astronomy.
Gavia FOV at 30x overlaid on Orion shows how comparatively narrow
it is.
The Moon
A
crescent Moon low in the dusk sky looked as crisp and detailed as it did
through the Harpia.
Mars
Mars was
the only bright planet around at the time of test and it looked like a minute
disk, with no flare or ghosting.
Deep Sky
The
Gavia has a really noticeably smaller field than the Harpia (see above). At 30x
it only just encompasses the main features of Orion’s sword, for example, or
just two of the belt stars where the Harpia easily manages all three.
The
Pleiades fitted perfectly in the field at 22x and looked quite good: not the
brilliant misty diamonds on velvet you get with an astronomical refractor, but
perfectly nice sharp stars.
The
Orion Nebula looked much as it does through an 85mm astro’ scope, with sweeping
arms of nebulosity and some whorls and clumps in the bright inner region. The
field of view at low power just about encompassed the whole of Orion’s sword.
Various
open clusters looked great, with the flat field framing them nicely among their
star fields – the Double Cluster, the Pinwheel, the Starfish and Praesepe all resolved into bursts of stars. I easily found
fainter and smaller clusters in the Milky Way in and around the constellation
of Cassiopeia.
Castor split
easily, but I failed to split Rigel.
Overall, the
Gavia makes a surprisingly good astronomical telescope and a very compact one,
but finding things is hard with no finder and a narrow FOV.
Zeiss Gavia 85 vs Tele
Vue TV-85
The TV-85 is a compact astro’ telescope that also gets quite
widely used for terrestrial viewing.
The TV-85 is just an ED doublet objective in a tube with a 2”
rack-and-pinion focuser (more recent versions get dual speed) and that
simplicity means it’s bright and capable of high powers. Despite the Gavia’s theoretical advantage of having an ED triplet, it
actually suffers rather worse false colour at high power and it’s not as sharp
above its design maximum of 60x (whereas the TV-85 will happily take well over
100x).
The ability to take 2” eyepieces means
the TV-85 has a much wider potential field of view too (up to ~4.4° vs 1.9°) and much greater flexibility for prime-focus photography.
However, the Gavia is much lighter weight, even more compact
and waterproof to boot; possibly more rugged.
So, for most terrestrial uses I would choose the Gavia as
expected, unless a wider range of field of view and/or power was a requisite. For
astronomy I would pick the TV-85 every time. For mixed use, the choice would
depend on specific needs (waterproofness etc).
Summary
The Gavia extends the Conquest vibe
into a scope – everything you need, nothing you don’t. Its huge advantage is
its light weight and compact size, even compared with the Harpia, but optically
and mechanically it’s mostly good news too.
The view is a bit narrow, but it’s
sharp to the edge, bright and crisp, with natural yet vibrant colours and truly
excellent resolution. The focuser is single-speed and a bit heavier and less
fluid than the Harpia’s, but is highly effective nonetheless.
Build quality is excellent on this
example. Contrary to expectations, if you didn’t know that it’s outsourced, you
would assume the Gavia is made in the same factory as the Harpia - it seems
very similar, even down to the coatings.
So the Gavia’s big downside isn’t lower optical or build quality,
as I’d feared it might be. Instead, the Gavia’s main
downside is its constricted view at low power that renders the already limited
zoom range (compared with the Harpia’s) much less useful still. The Gavia does
also show some false colour at high power, despite ‘HD optics’ and a triplet
objective, but I found this overall to be less of a problem than the limited
field of view.
The Gavia 85 gives a really outstanding view. Optical and
build quality are fully up to the high level you’d expect of Zeiss. The Gavia
is also very light and compact, just as advertised. Its main downsides are a
narrow field of view at low power and a bit of false colour the Harpia
eliminates.
Buy Zeiss Gavia 85 from Wex here:
