light metering

8/8/2019 Light Metering

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Meteringmaking your aperture & shutter speed worktogether to get a well exposed photo



Film Exposure ?

• film speed

what contributes to

Think about it like being out in the sun!

• aperture setting

• shutter speed

• film speed (sensitivity)

•aperture setting

• shutter speed

what is the weatherlike? how much sun isgetting to you?

how long are you out

in the sun?

how sensitive is yourskin? do you burneasily or tan easily?



f/2

f/18



most light

least light

f 2

f 4

f 5.6

f 11

f 16

f 22

1

2

4

8

15

30

60

125

250

500

1000



Think about a water faucet and a bucket. The faucet will act as the aperture and a timerfor the shutter speed. The bucket is a properly exposed photograph.

• When you open the faucet all the way (f/2), water rushes out so you fill the bucketin a very short time (1/1000 sec). This would let in a lot of light for a short time.

• When you open the faucet just a little bit (f/16), water barely trickles out and takesmuch more time (1/15 sec) to fill the same bucket.

• It doesn’t matter which combination you choose, the bucket is filled the sameamount, just like a photo can be exposed the same amount by various aperture

and shutter speed combinations while also controlling motion and depth of field.



Equivalent Exposures



ƒ2.8 @ 1/250 sec.

ƒ16 @ 1/8 sec.

These images make use of equivalent exposures - using differentsettings, they accomplish the same exposure - but with differentcreative effects!



f 2 f 4 f 5.6 f 8 f11 f 16

125


Point of Departure



f 2 f 4 f 5.6 f 8 f11 f 16

125


60



f 2 f 4 f 5.6 f 8 f11 f 16

125


60250



f 2 f 4 f 5.6 f 8 f11 f 16

125


60250 30



f 2 f 4 f 5.6 f 8 f11 f 16

125


60250500 30



f 2 f 4 f 5.6 f 8 f11 f 16

125


60250500 30 15



f 2 f 4 f 5.6 f 8 f11 f 16

125


602505001000 30 15



f 2 f 4 f 5.6 f 8 f11 f 16

125


602505001000 30 15

bracketing:shooting the same photo at different exposures



f 2 f 4 f 5.6 f 8 f11 f 16

125


602505001000 30 15

250 125 60




f 2 f 4 f 5.6 f 8 f11 f 16

125


602505001000 30 15

250 125 60


f 5.6 f 8 f 11



Using your camera’s internal light

meter to help you determine how toget a correct exposure.

LIGHT METERING

*

*some older cameras don’t have internal lightmeters - photographers with these cameras can

use external light meters



f/8125

not exposed

correctly



f/460

properly exposed



f/8125

+ too much light



- too little lightf/8500



correct exposuref/8

250



correct exposuref/8

250

f 2 f 4 f 5.6 f 8 f11 f 16 f 2

250 1255001000 60 30X



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Aperture Priority metering(you choose the f-stop it tells you the shutter speed)



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properly

exposed



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16

11

85.6

4

2.8

1.4

Shutter Speed Priority metering(you choose the shutter speed it tells you the aperture)

Too much

light



M

22

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11

85.6

4

2.8

1.4

Shutter Speed Priority metering(you choose the shutter speed it tells you the aperture)

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2.8

1.4

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0 11 22 +-

One stop overexposed

8 60



Your camera’s ROBOT EYE (a.k.a.the light meter/sensor) is trying tolook at what you’re photographingand find the MIDDLE VALUE.

THE ROBOT EYE

If you try to get a light meter reading from a reallydark or a really light area, your picture will notcome out well because the robot eye will think thatis the middle value.

Instead, try to meter from something IN THE SAMELIGHT as your subject, that really is a middle value.(Or you can use a grey card!)



1/40f 5.6

1/20f 5.6

metering from grey card



1/20f 5.6

metering from grey card

1/20f 5.6



iddl



middle grey



Focusing



split image focusing



split image focusing

Movement:



Movement:move the subject, move the camera, freeze the action

1/30



Point of View:get low, look down, turn sideways,get underneath, crop, zoom

light metering

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