Fujinon 10x70 FMTR-SX specs and field of view
An exit pupil of 7 mm and relative brightness of 49, both calculated, mark the 10x70 FMTR-SX as a night sky glass. It weighs 70.9 oz.
- Field of view
- 279 ftat 1,000 yd
- Eye relief
- 23 mm
- Close focus
- 65.6 ft
- Weight
- 70.9 oz
- Exit pupil
- 7 mmcalculated
Why pick it
- 23 mm eye relief, enough for glasses
- Waterproof
Who the 10x70 FMTR-SX suits
Astronomy suits its 70 mm objective, 23 mm eye relief and calculated twilight factor of 26.5. Individual focus holds a setting for distant targets.
A weight of 70.9 oz and a 65.6 ft close focus rule out handheld day use, and the 279 ft field is narrow.
10x70 FMTR-SX is one choice among many, and the top binoculars compared covers the most popular ones.
10x70 FMTR-SX specifications
10x70 FMTR-SX figures as Fujinon prints them; rows marked * are calculated from the 10x70 size.
| Magnification | 10x |
|---|---|
| Objective lens | 70 mm |
| Field of view | 279 ft at 1,000 yd (93 m at 1,000 m) |
| Angular field of view | 5.3° |
| Apparent field of view | 49.7° |
| Eye relief | 23 mm |
| Close focus | 65.6 ft (20 m) |
| Eye spacing range | 56 to 74 mm |
| Weight | 70.9 oz (2,010 g) |
| Width | 9.4 in (238 mm) |
| Waterproofing | 2m-5min |
| Focus system | Individual eyepiece focus |
| Exit pupil | 7 mm * |
| Twilight factor | 26.5 * |
| Relative brightness | 49 * |
* Calculated from the size, not printed by the maker.
Other sizes of the FMT (Polaris)
Fujinon makes the FMT (Polaris) in 4 sizes; a larger front lens adds brightness and weight, and more magnification narrows the view.
| Model | Size | Field of view | Eye relief | Close focus | Weight | Exit pupil |
|---|---|---|---|---|---|---|
| Fujinon 10x70 FMTR-SX | 10x70 | 279 ft | 23 mm | 65.6 ft | 70.9 oz | 7 mm |
| Fujinon 7x50 FMTR-SX | 7x50 | 393 ft | 23 mm | 32.2 ft | 49.7 oz | 7.1 mm |
| Fujinon 10x50 FMTR-SX | 10x50 | 342 ft | 19.8 mm | 65.6 ft | 50.4 oz | 5 mm |
| Fujinon 16x70 FMTR-SX | 16x70 | 210 ft | 15.5 mm | 168 ft | 67.7 oz | 4.4 mm |
Fujinon binoculars
10x70 FMTR-SX questions
10x70 FMTR-SX: does it work with glasses?
10x70 FMTR-SX has 23 mm of eye relief, which meets the 16 mm the RSPB advises for people who wear glasses.
10x70 FMTR-SX: what does 10x70 mean?
10x70 FMTR-SX magnifies 10 times through 70 mm front lenses, which works out to an exit pupil of 7 mm, the width of the beam of light that reaches each eye.