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3 Things Most Photographers

Don't Understand

You can be a good photographer without understanding the three things below.

But, why have three unsolved mysteries?

1 - Light Meters Are Stupid

Why?

The light meter in your camera gives you bad exposure settings when the scene is:

• Light colored and is in bright light.

• Dark colored.

Instead of light or dark, your photograph will be medium.

The solution is to use exposure compensation to modify the exposure.

White Board Example

Let's say you're photographing a white board.

The board fills the frame.

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White Board & Camera

You pop the flash up.

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Flash Up

You press the shutter release.

Let's keep things simple.

Let's say ten photons are heading toward the board.

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Ten Photons

When the ten photons hit the board:

• One photon is absorbed by the board.

• Nine photons are reflected back to the camera.

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1 Photon Is Absorbed

9 Photons Are Reflected Back

The light meter "sees" those nine photons and thinks the scene is bright.

It darkens the exposure.

The board looks white to us because it reflects lots of light.

Human vision is better than light-meter vision.

Our brains understand that objects absorb and reflect light at different rates.

When we look at a glacier in the sun, it's bright.

When we look at a black Duisenberg car, it's dark.

The light meter isn't able to see bright and dark objects as being bright or dark.

The light meter sees everything as being medium toned.

So, when photographing a white board, the light meter sees a scene that's too bright.

The light meter sets the lens opening and shutter speed to make the bright scene into medium-gray scene.

The white board will look gray on your LCD screen.

Black Board Example

Let's say you're photographing a black board.

The board fills the frame.

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Black Board

You press the shutter release.

The flash goes off.

Again, keeping things simple, let's say ten photons are heading toward the board from the flash.

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Ten Photons

When the ten photons hit the board:

• Nine photons are absorbed by the board.

• One photon is reflected back to the camera (in the red circle below).

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9 Photons Are Absorbed

1 Photon Is Reflected Back

The light meter sees only one photon and thinks the scene is dark.

It sets the lens opening and shutter speed to let in more light.

The black board will look gray on your LCD screen.

Solutions

The hardest aspect of the above situations is recognizing that a problem exists.

Your eyes won't see the problem until you're looking at the photograph.

Experiment by photographing a white car in the sun and a pile of black garbage bags.

Use one of the solutions below.

Solution #1 - Exposure Compensation

You can use exposure compensation to correct the light meter.

If the subject has light tones everywhere, and is in bright light, set the exposure compensation to +1.7 or thereabouts.

If the subject has dark tones everywhere, set the exposure compensation to –1.7 or thereabouts.

Solution #2 - Autoexposure Lock

You can also point your camera at something in the scene that's medium toned.

Worn pavement, green or brown grass, and the like, are medium toned.

Lock in the exposure and point your camera at the light or dark subject.

2 - Focal Length, Distant Backgrounds, & Depth-of-field

Depth-of-field is how much is in focus directly in front of—and behind—the subject.

The blur of the distant background is not determined by depth-of-field.

Focal length determines the blur of a distant background.

Let's look at this photograph.

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The lens opening controlled the depth-of-field—whether the girl was completely sharp or not.

The field and trees are blurry because a large focal length was used—such as 200mm.

Review

Depth-of-field is active around the girl.

Focal length affects the blur of the background.

Large focal lengths will blur more than smaller focal lengths.

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3 - Focal Length: Expansion & Compression

Most photographers zoom their lenses back-and-forth to change the composition.

If you don't want the trash can in the photograph, zoom in a little.

That's great.

Most photographers don't use focal length to play with volume and space.

Example

The slide below was photographed at 18mm and 300mm.

The image in the viewfinder is about the same in both photographs.

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Wide-angle: 18mm

Camera Was Close to the Slide

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Telephoto: 300mm

Camera Was Far Away from the Slide

Here are the photographs side-by-side.

In the 18mm-photograph:

• The slide is three-dimensional.

• The woods is far away.

 

In the 300mm-photograph:

• The slide is very flat.

• The woods is much closer.

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Review #1

Wide-angle Focal Lengths . . .

. . . expand volume and space.

Shapes become more shapely.

Backgrounds become further away.

Telephoto Focal Lengths . . .

. . . compress volume and space.

Shapes become flatter.

Backgrounds become closer.

However

It's not really the focal length that's doing the expansion and compression of volume and space.

It's how far the camera is from the subject.

When the camera is close to the subject, you get expansion.

When the camera is far away from the subject, you get compression.

The photograph below was taken from the same position as the 300mm photograph.

Here, though, the focal length was set to 18mm.

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 Position: Same as the 300mm Photograph

Focal Length: 18mm

If the slide is cropped out of the above 18mm photograph, it will look highly compressed.

The 18mm photograph has the same compression as the 300mm photograph.

Why?

If you're far away from the subject—the scene is compressed—whether the focal length is wide or telephoto.

Yup!

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Review #2

Let's look at the photograph below.

(Garish color—huh?!)

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If we were to photograph the cat at different distances:

• The cat will become bulgier or flatter.

• The background will become further away or closer.

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(My illustration has garish color, too!)

Summary

It's the camera distance that does the trickery.

Telephoto focal lengths just help a little by cropping the scene.