Nikon offers with its Prostaff 5 series a range of large lens binoculars, from 42 to 50 millimeters. With their weight and their wingspan thus higher than the average, these binoculars are rather intended for activities that require little movement such as ornithology, stationary observation, etc…
Their magnification of 12 is very suitable for a specific activity: astronomy. The 50 mm objective diameter captures a lot of light, which is crucial for stargazing.
Displayed at a price of less than $220, the Nikon Prostaff 5 12×50 has excellent optical quality.
This is what we are going to check in our test!
Nikon PROSTAFF 5 12×50 Reviewed & Tested
- Magnification: 12
- Lens diameter (mm): 50
- Perceived linear field at 1000 meters (m): 82
- Exit pupil (mm): 4.2
- Eye relief (mm): 15.5
- Brightness index: 17.6
- Minimum focusing distance (m): 5
- Dimensions (mm): 183 x 140 x 65
- Weight (g): 790
- Interpupillary distance (mm): 56 – 72
- Water resistance: 1 meter for up to 10 minutes
- Relatively low weight for 12×50 binoculars
- Good quality BaK-4 prism mirrors
- Few comatic aberrations
- Homogeneous brightness over the entire visual field
- Good color balance
- Little loss of sharpness on the edge of the image
- Few parasitic reflections
- Good ergonomics
- Compact and lightweight
- Average light transmission
- The multi-coated treatment of the lenses could have been better worked out
- Sensitive to chromatic aberrations
- Marked distortion at the edge of the lens
- Large dimensions can reduce maneuverability
- Protective lids that do not stay in place
Rugged Build and Decent Image Quality
The image definition is good on the Nikon Prostaff 5 12×50. Focusing is done over almost the entire field of view. A slight loss of sharpness appears on only 15% of the outline of the image, which is a good score.
The lenses exhibit relatively little astigmatism. This defect causes focusing relative to the horizontal to cause vertical blur and vice versa. Astigmatism can manifest itself when observing stars and planets: instead of appearing as points.
Another positive point, comatic aberrations are well controlled. They are only detected on 25% of the contour of the field of vision. They are concentrated mainly on the edges where the eye notices them much less.
As a reminder, comatic aberration creates a localized curvature of the image: a point then takes on the shape of a comma.
The great length of the Nikon Prostaff 5 12×50 could suggest that the lenses were mounted in doublets in order to reduce chromatic aberrations. Alas, the color defects are high, although the field of view is lower due to the high magnification.
Much of the chromatic aberrations appear in the center of the image. They are easily spotted by looking at an object against the light. The edges of the visual field are no exception either with a more pronounced color alteration than average.
By observing the contour, we also detect distortion. It appears on about a third of the image. This means that in this area the lines undergo a slight curvature instead of remaining straight.
Although it is normal to have distortion on binoculars under $220, it is higher on the Prostaff 5 12×50 than on other entry-level pairs such as the Delta-Optical Forest II 12×50 for example.
A passable but very homogeneous luminosity
The lenses are treated with a multi-layer coating that minimizes light loss between each lens. The exact type is not specified. However, it seems that only the outer lenses have their two surfaces treated.
The others probably only have a single-layer treatment or none at all. The prisms have a high-reflectivity coating based on aluminum, standard for binoculars of this price.
The result is quite mixed. The maximum transmittance of the Nikon Prostaff 5 is 12×50, that is to say, the percentage of light that reaches the eyes is just over 70%. This is a fairly low score, even for entry-level binoculars where it is common to exceed 80%. This is all the more astonishing since the lens diameter of 50 millimeters lets in a lot of light on its own.
The positive point is that the color rendering is very homogeneous. All colors in the visible spectrum are reflected with similar intensity. There are no dominant tones and there are no dull nuances. The brightness decreases a little away from the center of the image and the vignetting is not too pronounced.
Focus adjustment is excellent
Like all Nikon binoculars, the Prostaff 5 12×50 has an excellent focusing system. The focus wheel is large in addition to being easily accessible. It spins effortlessly and smoothly but retains the right stiffness to stop precisely at the optimal setting. You don’t feel any internal friction or backlash in the mechanism.
The adjustment range is over a turn and a quarter, which ensures a certain comfort of observation.
The diopter correction is done with a wheel placed under the right eyecup. It allows us to correct the possible defect of vision between the eyes. Without being too rigid, it has well-adjusted inertia. This keeps it in the desired position, without making it too difficult to turn.
The eyecups are adjustable in 4 levels to accommodate the most comfortable eye relief for the user. They stay in place once placed on one of the notches and they offer a good margin of adjustment.
Ergonomic and comfortable to use
In terms of ergonomics, the Nikon Prostaff 5 12×50 is doing very well. The rubber coating of the binoculars grips well in the hands. The tubes have a hollow shape on the outside, which allows you to place your fingers correctly for adding a touch of aesthetics.
The eyecups, also made of rubber, flatten evenly against the skin. They are still quite wide, which can be awkward for children with smaller faces.
In addition to their large size, the weight of these binoculars will not suit everyone. The Nikon Prostaff 5 12×50 weighs 790 grams, which is relatively light for binoculars of this caliber. They are nevertheless heavier than 10×32 or 8×42 binoculars for example.
Fatigue is likely to be felt more quickly on long outings. A solution will then be to install them on a support. The good news, the Prostaff 5 is compatible with mounting a tripod adapter, which is very useful for astronomy.
You will have the basic accessories when unpacking the binoculars: a padded neoprene strap, a storage case, lens protectors, and a cleaning cloth. The strap will not necessarily be of great use since we will not move much with this pair around the neck. Its quilted appearance will limit friction on the neck, which is a big plus for comfort.
The 15.5mm eye relief and 4.2mm exit pupil will allow you to enjoy an image that is easy to focus on the eyes, even if you wear glasses.
Good build quality with basic accessories
The Nikon Prostaff 5 12×50 gives an impression of solidity. The binoculars’ housing is made from fiberglass-reinforced polycarbonate. Although the term sounds daunting, it’s a pretty standard material for outdoor gear. The additional rubber sheathing offers better protection against shocks, which can be accentuated by the weight of the binoculars.
There are no collimation defects and the finishes are clean.
Nikon assures that the Prostaff 5 is waterproof to at least 1 meter depth for a maximum duration of 10 minutes. The inside of the tubes has been purged and then filled with nitrogen, which prevents the formation of fog on the prisms and glasses.
The accessories are nothing special, except that the eyepiece and objective protections are difficult to hold in place. We will replace them fairly quickly, or we will then be very careful not to unhook them when storing the binoculars in their case.
The visual field is 82 meters wide at 1000 meters distance. Without forgetting that a strong magnification decreases the visual field, it is a good score. It is the same value as the Celestron Granite ED 12×50, marketed at more than $500. Even if the panorama will be quite limited, you can keep an eye on the objects on the periphery.
The minimum focusing distance is a bit high
The minimum focusing distance is 5 meters. For 12×50 binoculars, this distance could have been a little lower. This pair will not be suitable for macro-observation (looking at objects at a very short distance). This is not the intended purpose anyway with a magnification of 12.
What use for the Nikon Prostaff 5 12×50?
These binoculars are ideal for beginners if you want to have a high magnification. For example, it is a good choice for observing nesting birds, stationary animals, or even stars and planets.
Keep in mind that the 12 magnification makes it difficult to track moving objects unless you are very far from your target. Likewise, the Nikon Prostaff 5 12×50 will not be suitable for use at sea where the waves will prevent you from keeping a stable image.
With a lens diameter of 50 millimeters, the Prostaff 5 have a significant size which does not make them suitable for carrying in a hiking backpack. We recommend this model more for activities that do not require a lot of movement.
The Prostaff 5 12×50 is a good pair of entry-level binoculars where Nikon had to find a compromise between quality and price. Outside, the Prostaff 5 is successful. The coating is pleasant to the touch, the adjustment is fluid and the grip makes the binoculars ergonomic to use. And even though they are very long, they are light. This is a big advantage.
As usual, protections for lenses are still neglected by Nikon, but this is not a critical point.
The overall sharpness is good in the center as well as on the edges. With little comatic aberration, consistent brightness and well-balanced colors, the Prostaff 5s perform well for astronomy.
However, the color defects are high and they are concentrated in the middle of the image as chromatic aberrations. The light transmission remains average, and the multilayer treatment of the lenses is not as qualitative as on other models at a similar price. The distortion appears quite quickly when moving away from the center of the image, which makes part of the field of vision less pleasant to look at.
However, we must not forget that the Prostaff 5 12×50 is sold at a very affordable price. By fixing them on a tripod, they will be ideal for learning to discover the stars or for observing nature from afar.
If we recommend this model, we still advise you to discover our test of…