.

AllBinos.com

Binoculars review

Carl Zeiss Conquest 8x56 T*

Carl Zeiss Conquest 8x56 T*
30 July 2010
Optyczne.pl 
The production of new Conquest binoculars was started at the beginning of the 21st century. At first it consisted of two models with quite uncharacteristic parameters of 12x45 and 15x45. Soon the Conquest series has been enlarged by the addition of 8x30 and 10x30 models. All of them were roof-prism Schmidt-Pechan devices.

Next instruments featured better Abbe-Koenig prisms, relying on the phenomenon of total internal reflection. In 2006 the 8x40 and 10x40 binoculars were added to the bunch and about one year later – the 8x50 and 10x50 models. The Conquest line-up became even bigger when in 2009 next two instruments, with the parameters of 8x56 and 10x56, were launched as well.

If you compare the Victory and the Conquest series you see that very expensive fluorite glass was abandoned, the field of view – a bit limited and the assembly lines were moved to the Hungarian Zeiss plant in MßtÚszalka near Debrecen. Because of that the binoculars of this series are even 50% cheaper than those from the Victory series, produced entirely in Germany. Their parameters and the quality of used materials still impress: 4-element objective lenses, all air-to-glass surfaces covered by the highest quality anti-reflection T* multi-coating, high-end prisms set in the optically efficient Abbe-Koenig system and additionally P* phase coated. All the binoculars are waterproof, shock-proof and nitrogen-filled and they come with 10-year quarantee.

Pictures
  • Lornetka Carl Zeiss Conquest 8x56 T*
  • Lornetka Carl Zeiss Conquest 8x56 T*
  • Lornetka Carl Zeiss Conquest 8x56 T*
  • Lornetka Carl Zeiss Conquest 8x56 T*
Manufacturer data

Manufacturer:

Carl Zeiss
web site

Distribution / Sales:

M.K. Szuster
web site

Magnification Lens diameter Angular field of view Prisms Eye relief Weight Price
8 56 110/1000(6.3o) BaK-4/roof 16 mm 950 g 5500 PLN
Results of the review
Real front lens diameter Left:   54.85+/- 0.05 mm
Right:  54.85+/- 0.05 mm
2 / 8.0 pkt
Real magnification 8.51+/- 0.05x 2/3.0
Transmission 86.8+/- 1% 14/25.0
Chromatic aberration Very low in the centre. At the edge a bit higher than medium. 6.8/10.0
Astigmatism Well-corrected. Nice point-like images of the stars with just slight „sparkling". 7.5/10.0
Distortion The distance of the first curved line from the field centre compared to the field of view radius: 45% +\- 2% 5/10.0
Coma Appears quite quickly because in the distance of 50-55% from the field centre. At the edge a bit higher than medium. 5.5/10.0
Blurring at the edge of the FOV The blur occurs in the distance of 73% +\- 3% from the field of view centre. 4/10.0
Darkening at the edge the FOV Slight but noticeable. 4.2/5.0
Whiteness of the image Not very flat transmission curve – too much light is lost in the blue part of the spectrum so the image becomes slightly yellow. 3.8/5.0
Collimation Perfect. 5/5.0
Internal reflections
Left: Right:
Carl Zeiss Conquest 8x56 T* - Internal reflections - Left Carl Zeiss Conquest 8x56 T* - Internal reflections - Right
Low. Circular pupil on a dark background.
4.5/5.0
Housing Very solid. Moderate dimensions for the 56 mm class. Very comfortable to hold and to look through. Rubber-coated eyecups with smooth regulation. The rubber armouring of a very high quality which fits tight, ensuring a good grip. It sticks out minimally near objectives. 7.9/8.0
Focusing Significant and comfortable central wheel. Moderately smooth, sometimes its work is too irregular. The full turn takes 700 degrees. Individual focusing of the right axis through the action of a wheel situated in a typical place of a tripod adapter – the wheel is moderately comfortable and a bit too tight. Nothing moves outside – inner focusing. 4/5.0
Tripod No. Optional tripod adapter. 2/3.0
Interpupilary distance from 57.2 to 75mm 5/6.0
Closest focusing distance 2.75 m. 2/2.0
Eyepieces FOV Apparent field of view of 53.7 deg (according to simple formula) and 50.3 deg (according to tangent formula). 6/20.0
Field of view Measured by us amounted to 6.31 +\- 0.03 degrees and it was in perfect accordance with the specifications within the margin of error. A typical field for this class of equipment. 5/8.0
Quality of the interior of the barrels Black and perfectly matt inner tubes and the bottom. Some small specks of dust on the prisms. 4.2/5.0
Vignetting
Left: Right:
Carl Zeiss Conquest 8x56 T* - Vignetting - Left Carl Zeiss Conquest 8x56 T* - Vignetting - Right
OL: 0.0%, OR: 0.0%
Nice circular pupils without any trace of vignetting.
8/8.0
Prisms quality High quality BaK-4. 8/8.0
Antireflection coatings Green-yellow on the objectives. Purple-pink on the prisms. Green-yellow-pink-blue on the eyepieces. Low intensity. 5/5.0
Warranty [years] 10 years 4.5/6.0
Final result
66.3%
125.9 / 190 pkt
Econo result 0pkt.

Summary


Pros:
  • very solid casing, extremely comfortable to hold,
  • good transmission,
  • decently corrected chromatic aberration,
  • slight astigmatism,
  • low brightness loss at the edge of the field of view,
  • perfectly circular exit pupils on a dark background,
  • high quality of prisms,
  • good coatings,
  • very good blackening of the binoculars inside the inner tubes.

Cons:
  • too small front lenses,
  • magnification bigger than declared,
  • the image at the edge of the field of view should have been sharper.


By and large from the very beginning I was an enthusiast of the idea behind the Conquest series. Not everyone can afford purchasing the high-end Victory series, characterized by the very expensive lack of compromise. In my opinion the launch of brand-name binoculars with the price tag 50-70% less than the same producer’s high-end models hit the nail on the head, especially that the main price-reducing factors of the Conquest series were harmless - moving the assembly line to Hungary and narrowing the field of view. These factors don’t hurt the optical performance. With the appropriate quality control implemented, you can produce a good instrument also in Hungary. The field of view is not a problem either, especially when it comes to the 8x56 class. In the case of these parameters the Victory series featured the field of view of 7.3 degrees – the biggest on the market. It could have been limited in the Conquest 8x56 without doubt and the obtained 6.3- degree field of view doesn’t lag behind the competitors anyway. For example the Docter Nobilem has a field of view of 6.3 degrees, the Steiner Night Hunter XP- 6.4-degree field of view and the Swarovski SLC New – 6.6 degrees.

The theory is one thing, let’s pass to practice now. Perhaps we should start with the transmission graph which is presented in the picture below.


The overall result is good but we still feel a bit dissatisfied. From such a company as Zeiss you can expect a bit more. Especially that 8x56 are typical night parameters so a high level of transmission is very important. The result near 87% in the centre of the visible spectrum for the Zeiss with Abbe-Koenig prisms doesn’t bowl us over. It’s enough to remind here the performance of the Docter 8x56 which reached near 95%. What’s more, the transmission curve of the Conquest is not very flat so there are slight problems with perfect whiteness rendition.

Our impression after testing the Conquest can’t be summarized easily – this set of binoculars is full of contradictions. On the one hand its build quality, well-chosen prisms which don’t truncate the pupils and don’t cause any brightness loss at the edge of the field, and ergonomics truly impress. On the other hand such a reputable producer surprisingly can’t follow parameters. The objectives aren’t even 55 mm in diameter, not to mention 56 mm. The magnification factor is rather 8.5 than 8 times. Additionally the limiting of the field of view, compared to the Victory series, gave some hope that the field of view would be very good even at the edges. It is not the case, though; it should have been sharper, with better coma and chromatic aberration correction.

The overall result of over 120 points is not bad. When you take the price into consideration though, it doesn’t bowl you over,. For such an amount of money you can have optically better and significantly cheaper Docter Nobilem 8x56 or 8x58 or the Steiner Night Hunter XP 8X56. What’s more, even Zeiss’s products can compete with the tested binoculars successfully because the Dialyt 8x56 model is also cheaper and better than the Conquest, presented here.