May 3, 2008

DIGITAL SLR CAMERAS


Here we go on another adventure in digital photography. We will venture into that freighting world of shutter speeds, and apertures. These are probably the hardest concepts of “how to” in the field of photography. Master these concepts and half of your battle for great pictures is behind you.

The shutter does two things; first, it controls the amount of time the light hits your sensor. The typical camera will have speeds in seconds such as 1, ½, ¼, 1/60, 1/250, etc. Your camera however, will show them as readings of 1, 2, 4, and 60. As you move up the scale, say from 30 to 60, you cut your exposure time in half. So, if you shorten the time the shutter is open, you shorten the light exposure.

Secondly, shutter speed controls motion. 1/15 of a second can make a moving subject look almost transparent while 1/100 of a second (and higher) begins to “freeze” or stop motion. Think about those water pictures you have seen. At 1/15 of a second, the water looked smooth and motionless but, at 1/100 of a second you could see the droplets begin to freeze in mid-air. Choosing the right shutter speed will give you the artistic effect you're after.

Tip: The shorter the exposure, the sharper the image.

The aperture also provides you with two functions. One is the control of light, and the other is depth of field. The aperture is measured in F-Stops. These are found on your lens and the speed of you lens (widest opening) will read as the smallest number- ex, f2.8. The smaller your aperture number, the more light you let in and the less depth of field you reach. The larger aperture numbers will reduce the amount of light while increasing your depth of field.

Tip: The shorter the focal length (18-50mm), the greater the depth of field.

These two mechanisms, work together in the creative art of photography. To produce a great picture you will need to learn how the two work in sync. Use the Amazon search box to the right for excellent digital photography books.

Until next time—Happy Shooting!

“The camera doesn't make a bit of difference. All of them can record what you are seeing. But, you have to SEE.” ~Ernst Haas, Comment in workshop, 1985

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