Binoculars review

Steiner Navigator 7x50

9 July 2014
If you look for marine binoculars the German Steiner company offers you two specialized series: the cheaper Navigator and the more expensive Commander. In both cases you deal with Porro prism 7x30 and 7x50 instruments, available with or without compass. Although the Steiner Navigator 7x50 is designed to be used near or on the water it should be made clear its parameters make it also a great device for work in poor lighting conditions (I mean here night hunting, astronomy, twilight observations or forestry).

The Navigator 7x50 is a huge and solid pair of binoculars with an individual focusing system. It is water-pressure proof down to a depth of two meters and it comes with a 10-year warranty period of the producer.

  • Lornetka Steiner Navigator 7x50
  • Lornetka Steiner Navigator 7x50
  • Lornetka Steiner Navigator 7x50
  • Lornetka Steiner Navigator 7x50
Manufacturer data


web site

Distribution / Sales:

Kaliber sp. z .o.o.
web site

Magnification Lens diameter Angular field of view Prisms Eye relief Weight Price
7 50 118/1000(6.7o) BaK-4/Porro ? mm 1055 g 1500 PLN
Results of the review
Real front lens diameter Left:   50+/- 0.05 mm
Right:  50+/- 0.05 mm
8 / 8.0 pkt
Real magnification 7.1+/- 0.05x 3/3.0
Transmission 85.4+/- 1.5% 13/25.0
Chromatic aberration Negligible in the centre, low on the very edge. 8.7/10.0
Astigmatism Medium. 5.5/10.0
Distortion The distance between the first curved line and the field centre compared to the field of vision radius: 69% +\- 4% 8/10.0
Coma Appears in a distance of 65% of the field and is medium on the very edge. 6.2/10.0
Blurring at the edge of the FOV The blur occurs in a distance of 89% ± 3% from the field of view centre. 8/10.0
Darkening at the edge the FOV Low. 3.9/5.0
Whiteness of the image Weak. A distinct transmission peak in the Middle of the range and a very noticeable loss in blue-purple light. 1.4/5.0
Collimation Perfect. 5/5.0
Internal reflections
Left: Right:
Steiner Navigator 7x50 - Internal reflections - Left Steiner Navigator 7x50 - Internal reflections - Right
Housing A big and solid Porro construction. Short but wide. High quality rubber armour. Fits well big hands. Rubber, folded eyecups. Nothing sticks out, nothing comes off. 8/8.0
Focusing Individual on both eyepieces. Small, ribbed rings. The scale ranges from -5 to +5 dioptres but you can exceed that even by two points. 5/5.0
Tripod No exit. In its place there are cup straps attached to the body. 0/3.0
Interpupilary distance from 56.4 to 74.4mm 5/6.0
Closest focusing distance 3.95 m 1.5/2.0
Eyepieces FOV Apparent field of view of 49.7 deg (according to simple formula) and 46.9 deg (according to tangent formula). 3/20.0
Field of view Measured by us amounted to 7.00 +/- 0.04 degrees and it was wider than stated in the specifications. A typical field for this class of equipment. 5.3/8.0
Quality of the interior of the barrels Dark tubes but with poor matting. Dark area near the prisms. In the left tube some specks of dust on the prisms; in the right the prism is very distinctly scratched. 2/5.0
Left: Right:
Steiner Navigator 7x50 - Vignetting - Left Steiner Navigator 7x50 - Vignetting - Right
OL: 1.51%, OR: 1.36%
Prisms quality BaK-4 glass prisms but weak near the edges. Some minuscule ‘diamonds’ visible even when you look straight on. When you look at an angle they become distinct. With the pupils straight on you get: OL: 2.95%, OR: 3.12% 4.5/8.0
Antireflection coatings Pink-purple on objective lenses and eyepieces. Some part of air-to-glass surfaces of prisms is most certainly not covered at all. 3.5/5.0
Warranty [years] 10 4.5/6.0
Final result
121.4 / 190 pkt
Econo result 0pkt.


  • very solid and waterproof casing,
  • very good correction of chromatic aberration,
  • negligible distortion,
  • moderate coma,
  • sharp image across almost all field of view,
  • low brightness loss of the image on the edge of the field of view.

  • prism optical elements lack coating,
  • truncated exit pupils, darkened on the very edge,
  • inside of the tubes leaves a lot to be desired.

I don’t hesitate to write here that I expected a lot from the Steiner Navigator and I was left disappointed. Nowadays for about 300-400 Euro you should be able to construct easily a great pair of Porro binoculars. I understand that the production of such a device in Germany is costly but you don’t deal here with anything overly complicated. A 7x50 model is a classic and with such a field of view the Navigator has it should be almost perfect.

Unfortunately Steiner decided to economize and they did it in a stupid way - anyway the employee responsible for the decision to save on coatings and leave one part of air-to-glass surfaces of the prisms uncovered should be fired. Even a cheap, Chinese Porro instrument, with a price tag of 100 Euro, features simple one-layer coatings on prisms. Why a renowned Steiner is worse than that is beyond my comprehension. As a result, however, the transmission graph of the modern Steiner is a dead ringer for that of old Zeiss Jena binoculars, produced some 30-40 years ago . It’s a shame.

The situation inside the tubes leaves also a lot to be desired. The binoculars are supposed to be produced in Germany but it seems the quality control was non-existent there. The darkening is hardly perfect, there are too many specks of dust; the scratch, clearly visible on one of the prisms, was the proverbial last drop of bitterness.

The Navigator has undoubtedly several advantages but stupid savings and shoddy workmanship made me privately very disgruntled. The successor of this device, the Navigator Pro, is being launched on the market right now. I just hope it will be devoid of the faults we discovered in this test.