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What is the camera’s meter used for?

Making Pictures With Professional Photographer John Enman
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The camera’s light meter is calibrated to measure light in a constant value and will distinguish the variation of reflection coming off different objects.

I have written about this topic before, but after talking to yet another photographer that had never used a camera unless it was in auto mode who asked me if I could explain what the camera’s meter does I decided I would revisit the topic.

In order for a subject to be captured by a digital camera it must be exposed to light.

This shouldn’t be new information to most; however, many photographers have problems understanding reflected light, exposure, and the camera meter, and rely on the (seemingly magical) automation technology built into digital cameras.

They are unaware that the sensor is actually reacting to the light reflected back to the sensor.

The camera’s light meter is calibrated to measure light in a constant value and will distinguish the variation of reflection coming off different objects.

Cameras have two mechanisms to control the amount of light reaching the sensor, the shutter, and the aperture.

Setting the camera’s shutter speed controls the length of time the shutter remains open. The aperture is an opening that lets light pass through the camera’s lens to the camera sensor.

What photographers are after is an optimal amount of light that will show details, in both the shadows and the highlights, and the camera’s meter is the way to determine and correct the under exposure or over exposure of those subjects.

My personal preference is to use the Manual mode. And I read the meter to help me set the correct exposure.

All DSLR cameras have light meters that are easy to read, those users that aren’t sure how to use their equipment should read the manual that comes with their camera.

There is one more feature on cameras that with practice helps to get that meter’s exposure just right. And that is the histogram on the camera’s LCD.  The histogram allows a user to check and correct a problem exposure immediately after releasing the shutter, and can save photographers from improperly exposed images.

Light meters on cameras have greatly improved over the years, and ignoring the camera’s meter information about the light, and relying on luck and preset auto modes, is a recipe for mediocrity.

To sum this all up, photography in practice is all about reflected light and my recommendation to photographers is to pay attention to the camera’s metering system, and to start using Manual mode.

Although it’s not the only way to get a workable exposure, using the Manual mode and the camera’s meter to manage shutter speed and the aperture gives the photographer control over how their photos are viewed and interpreted.

These are my thoughts for this week. Contact me at emcam@telus.net. Stop by Enman’s Camera at 423 Tranquille Road in Kamloops. I sell an interesting selection of used photographic equipment. Call me at 250-371-3069.