10x28 binoculars: 5 models compared

What 10x28 is used for

A 10x28 pair magnifies ten times through 28 mm lenses, a split the National Audubon Society explains as magnification first and objective diameter second. The exit pupil works out to 2.8 mm, and Nikon puts the eye's pupil at about 2 mm in daylight, so the view stays bright in good light.

Dusk is where the size gives ground. ZEISS says an exit pupil should be at least 4 mm for dawn use, and the twilight factor here works out to 16.7. Pick these for open daytime viewing, and see compact binoculars for the wider group of small pairs.

The RSPB suggests 10x for greater distances, and Celestron says a tripod is not required from 8x to 12x. That makes 10x28 a pocketable choice for long daytime looks without extra support. Audubon adds that higher power magnifies hand movement by the same factor, so a steady grip matters. For a larger lens at the same power, compare 10x32 or 10x42.

How the five models differ

Field of view separates them most. The GPO Passion SD 10x26 leads at 293 ft, and the Vortex Triumph HD 10x28 follows at 279 ft. The Maven pair sits at the narrow end with 262 ft, and it is the only model in the size with ED glass.

Weight runs from 11.6 oz on the GPO Passion SD to 13.3 oz on the Vortex Diamondback HD, against a median of 12.7 oz. Roof prisms are the most common type in the size.

Eye relief clusters near the median of 15 mm. Only 1 of 5 reaches 16 mm, the figure the RSPB gives as the minimum for eyeglass wearers, and that is the Vortex Diamondback HD 10x28. It also focuses down to 6 ft, as does the Steiner T1028, against a median close focus of 9.8 ft.

The Vortex Triumph HD 10x28 sits at 279 ft and 12.8 oz, close to the weight median, with a maker list price band of $100 to $200. The Maven C.2, Diamondback, Steiner and GPO all fall in the $200 to $500 band. Use the exit pupil calculator to compare this size with others.