Binoculars with a magnification of 10x, in my opinion, are the ultimate for handheld observation. Magnification over 10x already require an support, tripod or built-in image stabilizer. Binoculars of the 10×42 format are in stable demand, they are noticeably lighter and more compact than binoculars 10×50, but they have a greater magnification than similar ones in weight and dimensions of 8×42. However, making a good roof binocular is not an easy task. My attention was drawn to one of the top Olympus binoculars – 10×42 EXWP I. The binoculars were released a long time ago – the mentions I found go back to 2003. I was unable to find a press release on the release of this binoculars on the Olympus website.
Many of the Olympus models present in stores have been available since 2003 (for example, the Olympus 7×35 DPS I). In 2018, the new Olympus 8×42 Pro and 10×42 Pro binoculars with ED glass, dielectric coating, and improved illumination were presented.
Specifications declared by the manufacturer.
Prism type: roof with phase correction
Optical scheme: 9 elements in 6 groups
Environmentally friendly lead-free glass
Prism Material: High‑index BaK4 prisms
Coating: Full multi‑coating / Phase coating / UV coating
Aperture, mm: 42
Exit pupil, mm: 4,2
Eye relief, mm: 15
Relative brightness: 17,6
Real field of view, ° : 6
Visible field of view, ° : 60
Field of view at distance 1000 m, m: 105
Minimum focusing distance, m: 3
Dioptric correction: D ±2
Interpupillary distance, mm: 60–70
Focusing type: central
Eyecups: twist-up/down eyepieces
Gas filling: nitrogen
Size: 129 x 145 x 53 mm
Weight, kg: 0,66
The Olympus 10×42 EXWP I binoculars come in a simple and compact package. The set includes a case, binoculars, a case, lens caps, a double eyepiece cover, a belt and instructions. The case is of good quality, but very thin and does not protect the binoculars from shock. Belt 28 mm wide. The lens caps practically do not stick on the case, automatically removed when removed from the case.
Appearance, build quality
The case of the binoculars is black, matte, pleasant to the touch and comfortable. It looks stylish. The optics inside are clean, free of dust, fingerprints and stains. The approximate dimensions of the binoculars are 150 x 127 x 53 mm. Weight is about 600 grams.
In the front of the binoculars there is a plug for the tripod adapter, and on the plug there is a ring with a light accumulator – for the first time I see this among binoculars. Very original and interesting.
Focusing wheel with a diameter of 32 mm, ribbed, 24 divisions. Focusing is smooth. The full focusing range is one revolution with a quarter (about 450 degrees).
On the right eyepiece there is a ribbed ring diopter adjustment. The ring is tight, I did not like it.
The measured aperture is 42 mm. The lens flare is bright, green. There is a slight colorless flare from gluing. From prisms, glare is more dim, dark green.
Eyepieces glare green, lilac and blue. Eye lenses are large, measured diameter 22 mm. The measured size of the exit pupil is 4.3 mm. The left exit pupil is round, the right one is slightly cropped. The measured field of view of the eyepieces is about 56 degrees, the visible field of view of the binoculars is about 6.2 degrees.
Light protection is good. There is a small false exit pupil.
Eyecups inside plastic, outside rubber. Eyecups are twisted, 2 positions (twisted and untwisted). Eye relief from the untwisted eyecup is 12.5 mm. Eye lenses recessed 3 mm relative to the plane of the eyecup. For observation in glasses, the removal of the pupil at the limit is, in my opinion, due to the shape of the eyecups.
The through test showed the minimum yellowness of the image. Visual distortion of color reproduction is not observed. Very well.
Field sharpness is good, excellent on the axis. Approximately 80% of the field is clear, then the image is blurred due to the curvature of the field. After refocusing, the sharpness of the image at the edge is good, but the accommodation of the eyes is not enough to comfortably observe the object on the axis. When testing in the night sky, I liked the way the binoculars correctly reproduce their own color of stars.
Distortion is zero. Straight lines throughout the field remain flat, to the edge of the field of view the binoculars “compress” the image a little. If you smoothly guide the binoculars horizontally, then in certain scenes the image looks like a globe that rotates. This effect is called the “rolling ball” or “globe effect”. It occurs if the binoculars have zero or near-zero dystoria. To eliminate the “globe” is usually introduced a small pincushion distortion. In my opinion, in the Olympus 10×42 EXWP I binoculars the “globe effect” is weak and does not interfere with the observations – possibly due to the relatively small field of view of the eyepieces.
Fringing is low, but sometimes it is striking (for example, when observing white birds against a dark background in sunny weather). Color shifting is moderate.
The binoculars are very demanding on combining the exit pupils with the pupils of the observer, even with a slight shift throughout the field, noticeable blue halos appear, similar to the color fringing.
The image is saturated, chromatism is invisible. If you snuggle closer to the eyecups, a faint reflection on the Moon will be noticeable.
When testing on the moon, bright wide diagonal rays were discovered – for the first time I see this in roof binoculars.
The measured magnification of the binoculars from the images of the moon is 10x.
+ fully coated optics
+ bright, saturated and contrasting picture
+ sharp image over most of the field of view
+ low fringing
+ good color rendering
+ good blackening
+ weak reflections and ghosts
+ comfortable and ergonomic body
+ nice focusing
– the eye relief is too small, almost at the limit for observers with glasses
– the field of view of the eyepieces is less than the declared
– wide light rays when observing the Moon
– the need to accurately align the eyes with the exit pupils of the binoculars during daytime observations, otherwise strong chromatism occurs throughout the field
– tight dioptric ring of the right eyepiece
– egg-shaped right exit pupil
– lens caps do not stick on binoculars
– simple bag
I liked the binoculars and stay with me. I do not recommend observers with glasses. And so – in fact, this is an example of high-quality roof binoculars. If the flaws do not bother you – feel free to take it, it will not disappoint.
Also, thanks to the UV-coated optics, Olympus 10×42 EXWP I binoculars can be recommended for use in the mountains.