EXPOSURES (EV), FOOTCANDLES AND LUX, EXPOSURE FACTOR RELATIONSHIP

Exposure Values

EV TYPE OF LIGHTING SITUATION                
-6 Night, away from city lights, subject under starlight only.
-5 Night, away from city lights, subject under crescent moon.
-4 Night, away from city lights, subject under half moon. Meteors (during showers, with time exposure).
-3 Night, away from city lights, subject under full moon.
-2 Night, away from city lights, snowscape under full moon.
-1 Subjects lit by dim ambient artificial light.
0 Subjects lit by dim ambient artificial light.
1 Distant view of lighted skyline.
2 Lightning (with time exposure). Total eclipse of moon.
3 Fireworks (with time exposure).
4 Candle lit close-ups. Christmas lights, floodlit buildings, fountains, and monuments. Subjects under bright street lamps.
5 Night home interiors, average light. School or church auditoriums. Subjects lit by campfires or bonfires.
6 Brightly lit home interiors at night. Fairs, amusement parks.
7 Bottom of rainforest canopy. Brightly lighted nighttime streets. Indoor sports. Stage shows, circuses.
8 Las Vegas or Times Square at night. Store windows. Campfires, bonfires, burning buildings. Ice shows, football, baseball etc. at night. Interiors with bright florescent lights.
9 Landscapes, city skylines 10 minutes after sunset. Neon lights, spotlighted subjects.
10 Landscapes and skylines immediately after sunset. Crescent moon (long lens).
11 Sunsets. Subjects in open shade.
12 Half moon (long lens). Subject in heavy overcast.
13 Gibbous moon (long lens). Subjects in cloudy-bright light (no shadows).
14 Full moon (long lens). Subjects in weak, hazy sun.
15 Subjects in bright or hazy sun (Sunny f/16 rule).
16 Subjects in bright daylight on sand or snow.
17 Rarely encountered in nature. Some man made lighting.
18 Rarely encountered in nature. Some man made lighting.
19 Rarely encountered in nature. Some man made lighting.
20 Rarely encountered in nature. Some man made lighting.
21 Rarely encountered in nature. Some man made lighting.
22 Extremely bright, such as nuclear detonation.
23 Extremely bright, such as nuclear detonation.
  

 

Footcandles and Lux
There is a not intuitive relationship between EV, Foot-candles and LUX. EV is a linear measurement that is convenient to use for memorization of relative light levels. Footcandles and LUX proceed in a doubling manner, which better illustrates the doubling (or halving) of light at each step. To get to LUX, simply multiply the foot-candles by 11.

The table below (better) represents the relationship:
Exposure Value EV ISO 100 Footcandles LUX
-3 .03 .31
-2 .06 .63
-1 .12 1.3
0 .23 2.5
1 .46 5
2 .93 10
3 1.9 20
4 3.7 40
5 7.4 80
6 15 160
7 30 320
8 60 640
9 120 1300
10 240 2600
11 480 5100
12 950 10000
13 1900 20000
14 3800 41000
15 7600 82000
16 15000 160000
17 30000 330000
 

 

Exposure Factor Relationship  

FILM SPEED (ISO/ASA NUMBER) APERTURE OF LENS (f/STOP)
ISO 25 ISO 50 ISO 100 ISO 200 ISO 400 ISO 800 ISO 1600 ISO 3200 f/1.4 f/2.0 f/2.8 f/4 f/5.6 f/8 f/11 f/16 f/22 f/32
1 0 -1 -2 -3 -4 -5 -6 4 sec 8 sec 15 sec 30 sec 1 min 2 min 4 min 8 min 16 min 32 min
2 1 0 -1 -2 -3 -4 -5 2 sec 4 sec 8 sec 15 sec 30 sec 1 min 2 min 4 min 8 min 16 min
3 2 1 0 -1 -2 -3 -4 1 sec 2 sec 4 sec 8 sec 15 sec 30 sec 1 min 2 min 4 min 8 min
4 3 2 1 0 -1 -2 -3 1/2 sec 1 sec 2 sec 4 sec 8 sec 15 sec 30 sec 1 min 2 min 4 min
5 4 3 2 1 0 -1 -2 1/4 sec 1/2 sec 1 sec 2 sec 4 sec 8 sec 15 sec 30 sec 1 min 2 min S
E 6 5 4 3 2 1 0 -1 1/8 sec 1/4 sec 1/2 sec 1 sec 2 sec 4 sec 8 sec 15 sec 30 sec 1 min H
V 7 6 5 4 3 2 1 0 1/15 sec 1/8 sec 1/4 sec 1/2 sec 1 sec 2 sec 4 sec 8 sec 15 sec 30 sec U
8 7 6 5 4 3 2 1 1/30 sec 1/15 sec 1/8 sec 1/4 sec 1/2 sec 1 sec 2 sec 4 sec 8 sec 15 sec T
N 9 8 7 6 5 4 3 2 1/60 sec 1/30 sec 1/15 sec 1/8 sec 1/4 sec 1/2 sec 1 sec 2 sec 4 sec 8 sec T
U 10 9 8 7 6 5 4 3 1/125 sec 1/60 sec 1/30 sec 1/15 sec 1/8 sec 1/4 sec 1/2 sec 1 sec 2 sec 4 sec T
M 11 10 9 8 7 6 5 4 1/250 sec 1/125 sec 1/60 sec 1/30 sec 1/15 sec 1/8 sec 1/4 sec 1/2 sec 1 sec 2 sec E
B 12 11 10 9 8 7 6 5 1/500 sec 1/250 sec 1/125 sec 1/60 sec 1/30 sec 1/15 sec 1/8 sec 1/4 sec 1/2 sec 1 sec R
E 13 12 11 10 9 8 7 6 1/1000 sec 1/500 sec 1/250 sec 1/125 sec 1/60 sec 1/30 sec 1/15 sec 1/8 sec 1/4 sec 1/2 sec
R 14 13 12 11 10 9 8 7 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec 1/125 sec 1/60 sec 1/30 sec 1/15 sec 1/8 sec 1/4 sec S
S 15 14 13 12 11 10 9 8 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec 1/125 sec 1/60 sec 1/30 sec 1/15 sec 1/8 sec P
16 15 14 13 12 11 10 9 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec 1/125 sec 1/60 sec 1/30 sec 1/15 sec E
17 16 15 14 13 12 11 10 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec 1/125 sec 1/60 sec 1/30 sec E
18 17 16 15 14 13 12 11 1/30000 sec 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec 1/125 sec 1/60 sec D
19 18 17 16 15 14 13 12 1/60000 sec 1/30000 sec 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec 1/125 sec S
20 19 18 17 16 15 14 13 1/125000 sec 1/60000 sec 1/30000 sec 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec 1/250 sec
21 20 19 18 17 16 15 14 1/250000 sec 1/125000 sec 1/60000 sec 1/30000 sec 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec 1/500 sec
22 21 20 19 18 17 16 15 1/500000 sec 1/250000 sec 1/125000 sec 1/60000 sec 1/30000 sec 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec 1/1000 sec
23 22 21 20 19 18 17 16 1/1000000 sec 1/500000 sec 1/250000 sec 1/125000 sec 1/60000 sec 1/30000 sec 1/15000 sec 1/8000 sec 1/4000 sec 1/2000 sec
 

 

 

 

REMEMBER
  • A photographers rule of thumb:

    If your shutter speed is slower than the reciprocal of the focal length of your lens,
    you must use a tripod!

    Videographers should ALWAYS use a stand, if they don't film in wideangle!
    That is why I prefer to use a wideangle lens and/or at least a monopod!

  • Exposure values:  1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23
    Each number represents twice as much light as the numbers increase.

  • f-stops:  1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45
    Each progression represents half as much light (moving to the right) as the preceding number.

  • Shutter speeds:  15, 8, 4, 2, 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000, 2000, 4000, 8000
    Each number moving to the right is half the value of the preceding number, and represents half as much light as the preceding number.

    *****