I've just purchased a set of Cannon binoculars (10x30, IS) via Amazon. The directions that accompany them describe the alternatives for types of batteries to use for the image stabilization (IS). In part the directions read, "Although lithium batteries work well in low temperature, their performance will drop slightly in temperatures below 0 degrees C."
Let's not waste time fussing about "degrees C" instead of "degrees Celsius" or "°C". There is no explanation nor conversion to Fahrenheit applied to that statement about lithium batteries. Totally metric! If you don't get it, you should have stayed awake in your science classes.
Of course, the second figure in "10x30" is the objective lens diameter in millimeters. I daresay that many Americans don't know that.
In the specifications section of the English section of this multi-language booklet, however, the temperature range, size, and weight are given in metric, followed by a slash (/), and then by figures in inches, degrees Fahrenheit, etc. An exception to that is the field of view "at 1000 yds." which is specified as "314 ft.". This is a standard of the industry and I seem to recall that it is specified by ASTM. (In the other language sections, the field of view is given as 105 m at 1000 m.) The minimum focal length is given as "Approx. 13.8ft to infinity". (In the other language sections they specify 4.2 m.) The exit pupil diameter and eye relief distances are given only in millimeters (3 mm and 14.5 mm, respectively).
Most folks won't read the specifications page. They are much more likely to read just the few pages of directions and there they will not encounter any non-SI units.
Jim -- James R. Frysinger 632 Stony Point Mountain Road Doyle, TN 38559-3030 (C) 931.212.0267 (H) 931.657.3107 (F) 931.657.3108
