10x50s occupy the “sweet spot” for hand-held binoculars, and the Opticron Adventurer offers a very inexpensive way to dip your toes into this rewarding pastime.
Pros: Some impressive features for budget binoculars
Cons: Some typical budget-bino constraints remain
The initial impression of the Opticron Adventurer is of a no-nonsense and no frills instrument. Mechanically, everything works as it should, with the only negative being slight “stiction” when the focuser, hinge, or right eyepiece diopter haven’t been used for a while.
The textured rubber armor provides a secure grip, even with woolen gloves. Optically, we have fully coated lenses, single-coated BK7 prisms, a free aperture of 47 mm (42 mm or less is common in budget 10×50 binoculars), and sufficient eye relief for eyeglass wearers.
There is a comfortable 30 mm (1.2 inches) wide webbing neck-strap, to which you can tether the well-fitting rainguard-type of eyepiece cover. The plug-in objective covers have split tabs that enable you to thread them onto the strap as well. The slightly-padded soft case is more for storage than protection.
The coatings appear to be evenly applied, and reflect only a small amount of light. There are no baffles in the objective tubes, so stray light is not well controlled, and you get spurious reflections if a gibbous Moon is within about 5 degrees of your field of view.
However, the overall optical quality is surprisingly good for low-end binoculars. Stars are very sharp over the central three quarters of the field of view, and we could split Albireo (Beta Cygni) and see its color contrast over all but the outer 10 percent. Nearby, the Dumbbell Nebula (M27) was a tiny rectangular smudge, and the oval glow of the Andromeda Galaxy (M31) was denser in the middle and spread across a third of the generous 6.6 degree field of view.
False color (chromatic aberration) is well-controlled on axis, but the lunar terminator showed color when it was even slightly off axis. First magnitude stars were only affected towards the edge of the field.
All binoculars at this price-point will have “issues”, and the most notable drawback of the Adventurer is the poor control of stray light, but that’s not really a problem over most of the sky. The favorable points more than compensate for this. When I listened to the voice recordings that I made when testing, I became aware of how many times I muttered something akin to “this is a really nice little bino”. It is.
Good value for money, both for casual users and for newcomers to binocular astronomy.
Original review: http://binocularsky.com/binoc_reviews.php
MSRP: Discontinued by manufacturer. Available at some dealers.