Nikon Tundra 10x50 CF WP
Exactly such a situation was the reason why we’ve ordered the Nikon Tundra 10x50 CF WP model for testing. It costs around 250 Euro so it is a bit more expensive than the Action EX. If it happens to be also a bit optically better, the hole in the price segment of 220-500 Euro might prove to be a bit smaller than I thought at the beginning. Paradoxically, looking at its technical specifications, the Nikon Tundra 10x50 CF WP doesn’t offer much more than the Action EX binoculars. You can notice it consulting the following chart. The Tundra features a narrower field of view (although you must remember that the Action’s EX field of view is in fact smaller than that stated in specifications) and it is physically heavier. Both pairs of binoculars are waterproof up to a depth of one meter so here there is a draw in this category. As the Nikon Tundra is more expensive it might suggest better optical properties. Is it really the case? We are going to find out after a while.
| Magnification | Lens diameter | Angular field of view | Prisms | Eye relief | Weight | Price |
|---|---|---|---|---|---|---|
| 10 | 50 | 108/1000(6.2o) | BaK-4/Porro | 17.4 mm | 1065 g | 949 PLN |
| Real front lens diameter |
Left: 50+/-
0.05 mm Right: 50+/- 0.05 mm |
8 / 8.0 pkt | ||||
|---|---|---|---|---|---|---|
| Real magnification | 10.77+/- 0.05x | 2/3.0 | ||||
| Transmission | 86.9+/- 1.5% | 14/25.0 | ||||
| Chromatic aberration | Low in the centre, medium on the edge. | 7/10.0 | ||||
| Astigmatism | Slight. | 7.5/10.0 | ||||
| Distortion | The distance of the first curved line from the field centre compared to the field of view radius: 50% +\- 3% | 5/10.0 | ||||
| Coma | Appears in the distance of 70% from the field of vision centre and is medium on the very edge. | 7/10.0 | ||||
| Blurring at the edge of the FOV | The blur occurs in the distance of 69% +\- 3% from the field of vision centre. | 3/10.0 | ||||
| Darkening at the edge the FOV | Negligible. | 4.7/5.0 | ||||
| Whiteness of the image | Very good but the blue colour transmission could have been higher. | 4.5/5.0 | ||||
| Collimation | Perfect. | 5/5.0 | ||||
| Internal reflections |
|
1.9/5.0 | ||||
| Housing | A big and classic Porro device. Gray, quite smooth rubber padding. It is comfortable to hold. Rubber folded eyecups. The rubber sticks out near the objectives.. | 5.8/8.0 | ||||
| Focusing | Small, deep hidden central wheel, uncomfortable and slippery. Full turn through 400 degrees. Ocular bridge a bit hidden as well, but moves evenly with a bit of sideways play. Pressure on the bridge doesn’t make the device defocused. Individual focusing on the right eyepiece; it moves the outer element. | 3.3/5.0 | ||||
| Tripod | There is a comfortable exit which supports the straps with objectives’ caps attached. | 3/3.0 | ||||
| Interpupilary distance | from 54.5 to 73mm | 4/6.0 | ||||
| Closest focusing distance | 5 meters. | 1/2.0 | ||||
| Eyepieces FOV | Apparent field of view of 65.5 deg (according to simple formula) and 59.5 deg (according to tangent formula). | 14/20.0 | ||||
| Field of view | Measured by us amounted to 6.08 +\- 0.04 degrees and it was a bit narrower than that stated in specifications. | 5/8.0 | ||||
| Quality of the interior of the barrels | Inner tubes black and matt, the bottom is gray. A lof of white glue near prisms. Some very tiny specks of dusts. | 3.1/5.0 | ||||
| Vignetting |
|
4.5/8.0 | ||||
| Prisms quality | Good quality BaK-4. | 8/8.0 | ||||
| Antireflection coatings | Greenish on objectives, although the inner side seems to remain uncovered. Purple on prisms. Greenish on eyepieces but here also it seems that either on one surface the coating is a bit weaker or that surface is not covered at all. Medium intensity. | 3.5/5.0 | ||||
| Warranty [years] | 10 | 4.5/6.0 | ||||
| Final result | 68.1% | 129.3 / 190 pkt | ||||
| Econo result | 0pkt. |
Summary
Pros:
- good correction of chromatic aberration,
- slight astigmatism,
- well-corrected coma,
- negligible brightness loss on the edge of the field,
- decent colour rendering,
- good quality of prisms.
Cons:
- magnification significantly better than declared,
- part of air-to-glass surfaces seems not covered,
- truncated exit pupils,
- a lot of flares in the area near exit pupils,
- small, deeply hidden central wheel,
- image resolution on the edge of the field should have been better.
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I think we have a surprise here. A bit cheaper Nikon Action EX not only is physically lighter, although as solidly build as the device tested here, but also fares better. The difference is perhaps not huge but still noticeable. What’s interesting, the coatings, implemented here, influenced the performance. It seems that in a more expensive model we should deal with better antireflection coatings. A transmission graph, shown below, and a detailed inspection of the inside of the tested binoculars tell us a different story.
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Currently, a good Porro device shouldn’t have problems with its transmission level exceeding 90%. Most often there are no such problems if only all air-to-glass surfaces feature multilayer antireflection coatings. It is not the case of the tested Tundra. It seems that not one but two surfaces are either coated by a layer of inferior quality or not coated at all. At such a price point it simply shouldn’t have happened.
To sum up, I really would be hard-pressed to find any rational reason why you should spend additional Euro and buy the Tundra instead of the Action EX. One more thing at the very end. This pair of binoculars often is presented in shops as the Nikon 10x50 CF WP without the addition “Tundra”. It was listed in such a way also in our binoculars’ database for a long time – everything because on the original Nikon site the word “Tundra” doesn’t appear at all. It can be seen�here. However, when the binoculars arrived to our editorial office, we saw the following box.
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