Nikon 10×42 SE

 Binomania readers know very well my predilection for porro prism binoculars: their three-dimensionality, their excellent performance in proportion to the purchase price, and the reduction of aberrations have always made me prefer them, at the same price, to roof prism binoculars.

 Characteristics

Magnifications (X)	10
Diameter (mm)	42
Prisms	Porro Bak-4 Prisms
Optical hull	Magnesium
Royal Field	6th
Apparent field	60°
Field at 1000m	105m
Exit pupil (mm)	4.2mm
Twilight Factor	17.6
Eye relief (mm)	17.4
Minimum focusing distance (m)	5
Measurements (mm)	157 x 192
Weight (gr)	710

For this reason I was very curious to test the Nikon 10×42 SE, especially because overseas they seem to be binoculars widely used for nature observations.

Construction and Mechanics:

The Nikon 10×42 SE uses a chassis made of magnesium, making it particularly resistant and lightweight, just over 700 grams.
The ergonomics typical of porro prisms make it an easy to hold binocular, with a secure grip, personally, with these binoculars that provide 10x magnification, I am able to contain vibrations, similarly to my example of Kowa Prominar 8.5X44 equipped with roof prisms.

My arms remain wide and I can distribute my weight more, reducing vibrations, even after a long trekking session.

When using trekking poles, it is very convenient to use one as if it were a light monopod.

Furthermore, the binoculars are perfectly balanced. The non-slip rubber coating is functional, even with sweaty hands and gloves, and the finish is very refined.

The binoculars were collimated and even in stargazing, where this defect is more noticeable, I did not perceive any annoying misalignment.

Unfortunately, although the binoculars were designed for nature use, they are not perfectly tropicalized, in fact the Nikon 10×42 SE is not able to withstand a JIS immersion test, but can resist, at most, a light rain.

This is also noticeable from the external focusing which, with the exception of the Swarovski Habicht, the only ones to have a waterproof central carriage, seems to be able to be simply defined as “splash proof”.
Talking with a couple of overseas birdwatchers, I was confirmed that they never had problems observing under a slight

A little rain, but these are certainly not the kind of binoculars you can wash under running water. The rubber eyecups can be lowered to provide greater eye relief for eyeglass wearers, but in certain circumstances, especially in bright light, you'll need to move your face slightly back from the binoculars to avoid what Americans call "binocular blackout."“

The interpupillary distance is adjustable from 56-72mm while focusing proved to be fast and precise, without any play in the movements.
Furthermore, the binoculars have a minimum focus of only 5 meters, which is greater than that of binoculars with roof prisms, with the same magnification. This feature could create problems for those who like to observe insects and animals at very close range, but being a 10X with porro prisms, there would, obviously, be the certainty of obtaining double images.
To gain further insight into my assertion, I'm quoting part of a text excerpted from an old article of mine, which you can read in the box below.

BOX MANY READERS WILL HAVE NOTICED THAT WHEN OBSERVING VERY CLOSE SUBJECTS, THE IMAGE PROVIDED BY THE BINOCULARS TENDS TO SPLIT UP, IN A KIND OF "EIGHT". THIS DEPENDS ON TWO FACTORS: THE DISTANCE OF THE OBJECTIVES FROM EACH OTHER AND THE PREVARICATION OF THE PREVARICATED EYE WITH RESPECT TO THE OTHER WHICH HAS THE BEST, PRECISELY IN THIS TEMPORARY FACTOR AND WHICH DOES NOT ALLOW THE BRAIN TO TOTALLY INTEGRATE BOTH IMAGES. THIS DEFECT IS EXTREMELY OBVIOUS TO THOSE WHO ARE USED TO OBSERVING DETAILS WITH ONLY ONE EYE, A TELESCOPE AND/OR A TELESCOPE, SINCE THE BINOJECTOR'S EYE-BRAIN SYSTEM SEEMS TO BE MORE TRAINED. FOR THIS REASON, SINCE PORRO PRISM BINOCULARS ARE EQUIPPED WITH OPTICAL TUBES THAT ARE FAR MORE APART FROM EACH OTHER, COMPARED TO THE OPTICAL TUBES OF ROOF PRISM BINOCULARS, PORRO PRISMS GENERATE A GREATER DOUBLING OF THE IMAGE, TO THE DETRIMENT OF NATURALISTIC OBSERVATIONS AT SHORT DISTANCE, FOR THIS REASON IT IS DECIDEDLY MORE PLEASANT TO OBSERVE INSECTS AND BUTTERFLIES AT SHORT DISTANCE WITH ROOF PRISM BINOCULARS, COMPARED TO PORRO PRISM BINOCULARS

Optics:
 Lenses and prisms

 Nikon doesn't disclose the composition of its lenses, but based on their performance, I'd call them "low dispersion." As I've often pointed out on the site, it's impossible to make a comparison between different ED optics, as I've tested countless binoculars with dissimilar characteristics.
Thanks to the 60-degree apparent field, wide angle eyepieces have proven to be a valid compromise between the containment of aberrations and sharpness. Sometimes, the presence of scattered light is noticeable near the edges, in some lighting conditions, but I consider this to be limited and not capable of affecting the contrast of the image provided at the center of the field.

Prisms
They are high refractive index BAK4 prisms, equipped with multi-layer treatment

Field curvature

The binoculars have only a slight curvature of field, to achieve a sharp image at the edge, after focusing the area
Central, it only takes 1/8 of a turn of the knob, which is a mere trifle. I would describe these binoculars as having an almost perfectly flat field. In this respect, I consider both the 8x32SE and the 12x50SE versions to be better.

Angular distortion
The Nikon only shows a slight angular distortion capable of compensating for the classic rolling ball effect during the panning phase.
A factor confirmed in this case too, by the omnipresent test carried out by observing a lamppost and in practical use.

Exit pupil
The Nikon 10×42 SE has two perfectly spherical and uniform exit pupils, with perfect uniformity of illumination even at the edges.

Prism cut-off
Absent

 Chromatic aberration

The chromatic residue is perceptible only in very strong lighting conditions and on backlit subjects, under normal conditions of use,

chromatic aberration, on the other hand, is non-existent in the centre of the field and is only perceptible at its extreme edges with the classic faint blue-green halo,

definitely not annoying. Overall, it's a sharp, bright, neutral image... in short, I'd call it "clear," better than that,

for example, the HG roof series, with roof prisms, with warm tones and a greater chromatic residue.

             
Anti-reflective treatment.

It seemed very good to me. With mere visual analysis it appears perfect and free of streaks, attempting to reflect the page of a newspaper, it shows very few details, a factor that denotes the high capacity of the treatment to send light to the prisms, without dispersing it. .

It is one of the best treatments that I have had the opportunity to test in practical use.

 Brightness

Despite the diameter of only 40mm, these binoculars are very bright, so much so that I also appreciated them when observing constellations, where I did not notice any particular differences with binoculars with the classic 10×50 except for the weight, which is definitely in favor of the small Nikon.

 Practical use

 I used these binoculars for about three months, often taking them with me on nature trips, but also using them at home and in the mountains to observe the sky.
I had the opportunity to compare it with my Kowa 8.5×44 (ROOF) and the Minox BP 8×44 BD (PORRO), with a Minox 8×42 BD series (ROOF), with a General Hi-T 10×50 (PORRO) and with a Swarovski 8×50 SLC. (ROOF) I am aware that these are merely impressions given that the binoculars have different characteristics from each other, but such indications are always welcome and requested by many readers, so I decided, in this case too, to cite them in the review, even if they do not have the value of a reliable comparison.

Overall, I appreciated the 6° field of view, which is an excellent compromise between immersion in the scene and minimizing various aberrations, its light weight, and the decidedly good optical performance. I preferred not to use it in snow and rain, due to the aforementioned lack of waterproofing, but I am aware that not all users enjoy spending their free time in the cold and rain only to glimpse a deer or roe deer.

I now move on to describe my practical impressions in the various sectors of use.

Birdwatching.

I appreciated the 10X magnification which often makes the difference in recognising the observed species, also the enviable optical performance is

perfect in this sector, where purity of images and a good ability to make subjects recognisable even in the presence of strong backlighting are required.

I really appreciate the neutral rendering of these binoculars and in certain situations they did not make me regret the much more expensive roof binoculars.
Any comparisons? The Kowa 8.5x44 provides an image free of chromatic aberration, while the Nikon has a more three-dimensional image, the Minox BD 10x44BP is the sharpest in the center of the field, but has a very small apparent field, while the Swarovski 8x50 SLC is bright and very correct, but is decidedly heavy.

Astronomy

It is a nice light binocular, for fleeting observations of the constellations and some bright objects, under an average sky you can observe the M42 Nebula,

the various winter star clusters, and the brightest galaxies, all obviously perceptible as small flakes of light, with the comet Lulin clearly visible.

For astronomy lovers, I can say that the almost flat field provides a very correct image up to about 80% of the field, after which you notice the presence of coma that transforms the stars into small lines... but I must say that the overall performance is very good.

Any comparisons? The General Hi-T has more pinpoint stars, but less correction at the edges of the field of view and is heavier than the Nikon,

the Nikon is a middle ground between lightness and brightness, even the focus, despite being composed of a central carriage, is free of play and very precise, on the other hand, although the Swarovski SLC 8×50 should win in brightness, thanks to the 50mm diameter, the 10x magnification provided by the Nikon 10×42 allowed me to better appreciate deep-sky objects, such as M42, M51, M31, M101 etc etc. A clear coma appears at the edges, which I remember not being visible in the 12x50SE version, preferred by many amateur astronomers.

Land use


I believe this is its sector, where it ranks among the best binoculars I've tested. Light enough to be carried at high altitude, it provides very good immersion in the landscape, the focus is precise, it can even handle situations with the sun near the framed landscape circle and the field is almost flat, and it provides a realistic and pleasant image.

Any comparisons? Even in this case, the Kowa 8.5×44, although it produces a less three-dimensional image, provides a better ability to contain chromatic aberrations, similar to the Swift 8.5×44 which, however, has an enviable field of view, almost close to the declared 8°. The Nikon 10×42 SE, however, is better than the Kowa 8.5×44 in containing reflections, and is more correct at the edges than the Swift, the Minox BP 10×44 BD is a chisel in the center of the field, but has a smaller real field of view, equal to 5°.

  In summary

I would define the Nikon 10×42 SE as an excellent binocular for terrestrial use, valid for medium-long distance observations of animals and birds.

I reiterate that when the quality is very high, often the differences between one binocular and another derive from purely subjective factors, however the certain thing is that in terms of mechanics, optical quality and brightness the Nikon 10×42 SE is rightfully placed among the porro prism binoculars that I prefer most.

 Advice to the builder?

Very few: I would review the eyecup system and try to improve the waterproofing. A Nikon 10x42 SE with internal focusing and the excellent optical quality of the 12x50SE and 8x32SE wouldn't be bad... but perhaps that would be asking too much.

Disclaimer: This review was published in August 2010. Please note that the user impressions are entirely personal and provided by Binomania testers in complete freedom, without any commercial obligation or relationship, and based on proven experience using these optical instruments. For any information, updates, and/or changes to prices, instrument features, authorized sales outlets, or other information in general, please contact Nital Spa directly by clicking on the image below.