Binoculars

Question 1

Magnification: The first number =

Answer 1

how much larger or closer an

image appears

Question 2

Aperture: The second number =

Answer 2

Diameter of the objective lens (larger end of the

binocular)

Question 3

Compact ____ mm

Full size _____ mm

Answer 3

20-25

35-50

Question 4

Field of View

Answer 4

The widest dimension you can see across a circular view.

As magnification increases field of view decreases

Question 5

Linear measurement range from

Answer 5

263-578’ at 1000 yds

Question 6

Angular measurement

Answer 6

5-11 degrees

Question 7

Covert

Answer 7

1 degree = 52.5’ at 1000 yds

Question 8

Eye relief

Answer 8

distance where
images projected from ocular
lens to their focal point.

5-23mm

Question 9

Exit pupil

Answer 9

is the size of the
image as it leaves the
eyepiece to enter your eye

Question 10

Eye pupil in
bright light = __ mm
in dim light = __ mm
in dark = __ mm

Answer 10

2-3mm
4-5mm
6-8mm

Question 11

Recommend exit pupil of at

least

Answer 11

4mm

Question 12

Divide diameter of objective

lens by magnification to get

Answer 12

Exit pupil

Question 13

Coatings decrease

Answer 13

amount of light absorbed and
refracted by lens.

High quality optics allow 90%
of light to reach eye.

Question 14

Coated lenses

Answer 14

one or more surfaces of one or

more lenses received coating

Question 15

Fully coated lenses

Answer 15

one or more surfaces of one

or more lenses coated with multiple films

Question 16

Fully multi-coated lenses

Answer 16

all air to glass surfaces

have multiple films

Question 17

Focus

Answer 17

Use center focus