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#4 - Lens Opening

As mentioned in the last assignment, the #1 complaint of most photographers is:

My photographs aren't sharp!

So, cameras are designed to use small lens openings, such as f/16, to make sure every photograph is sharp.

The camera focuses on the subject, so it's in focus.

But, because of the small lens opening, such as f/16, there's more depth-of-field.

There's more that's acceptably sharp in front of, and behind, the subject.

You can make some photographs great by using a wide lens opening to blur the background.

Read your instruction manual to find out how to change the lens opening.

Look for the three methods below.

Three Methods

Note

Digital photography is great, but it's not 100% great.

With film cameras, one was able to blur the background easily.

Most digital SLR cameras are unable to blur the background as much as film cameras.

Argh!

Point-and-shoot cameras have even more difficulty blurring backgrounds.

Everything is always in focus

Argh!

1 - Flower & Face Icons

Flower Icon

If your camera has a flower icon on the exposure mode dial, the camera will use the smallest possible lens opening.

Use the flower icon when doing:

• A close-up

• A portrait in which you want the background to be more in focus.

Face Icon

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If your camera has a face icon on the exposure mode dial, the camera will use the largest possible lens opening.

Use the face icon when doing:

• A still life in which you want the background to be more out-of-focus

• A portrait in which you want the background to be more out-of-focus.

2 - A or Av

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Digital SLR cameras, and some point-and-shoot cameras, have a aperture-priority mode setting (A or Av).

With the aperture-priority exposure mode, you select the lens opening, and the camera selects the shutter speed.

By choosing the lens opening, you can determine the optimum setting.

Digital SLR Cameras

Set the lens opening to f/4 on your lens for little depth-of-field.

If you're doing lots of portraits, and you want to blur the backgrounds even more, use a 50mm f/1.4 or a 50mm f1.8 lens.

If there's enough light, set the lens opening to f/22 or f/29 for the most depth-of-field.

Point-and-shoot Cameras

The lens opening on your camera goes from about f/2.0 to about f/5.6 or f/8.

Unfortunately, even at f/2.0, there's lots of depth-of-field.

Your camera doesn't have smaller lens openings, such as f/11, f/16, and f/22.

That's because the diffraction would be too great with these small lens openings.

3 - Scene Modes

As mentioned in the last assignment, many point-and-shoot cameras have scene modes.

There may be scene modes for close-ups and for portraits.