AboutJim Delillo Expertise ALmost any question about traditional (film) or digital photography including techical, technique, lighting, darkroom, Photoshop, marketing and business.
Expert: Jim Delillo Date: 7/3/2008 Subject: DSLR photography
Question Hi there,
How do i take meter reading with a DSLR camera.i've read different photography mags where people have said about taking a meter reading to set the camera,but i have no idea how to take one or what i would do with even if i had. Thanks John.P.S i have Canon 30d.
Answer First remember that any light meter is going to take an average of the scene to render it 18% gray.
Digital SLR usually have several meter modes.
Matrix - a proprietary formula looking at all the pixels
Center-Weighted - Favors proper exposure of the subject in the center (circle)
Spot - Favors proper exposure for the subject targeted in the dot.
Your DSLR is always using its meter.
To activate the meter press your shutter button half way down.
In any automatic mode:
Auto (usually identified with a green icon)
Programmed
Aperture Priority - You set the Aperture and it sets the Shutter Speed
Shutter Priority - You set the shutter speed and it sets the Aperture.
Your 'Exposure Compensation' button allows you to adjust the camera to give a picture darker or brighter than the meter would. This is especially helpful in sand/snow, where the meter, rendering an 18% gray would make the snow look dirty. You would add +2 to your exposure compensation allowing two stops more light to the sensor.
But to "Use the meter" as in your original post, in a DSLR you must set your camera to 'M' - manual mode.
Your meter indication will be shown in the viewfinder as a series of tick marks. Adjusting either the aperture or shutter will move the cursor. When the cursor is on the center tick mark it is "properly exposed", that is it is rendering the scene to 18% gray based upon the meter.
While in manual mode you can set the camera to something other than a centered cursor. By setting either the aperture or shutter speed you will cause the cursor to move in the direction of + or - depending on which way you are adjusting the exposure.
Higher aperture numbers (towards f22), without a corresponding change in shutter speed will darken the image and increase depth of field.
And just the opposite.
Higher shutter speeds (towards 1/1000), without a corresponding change of aperture will darken the image and reduce motion blur without affecting depth of field.
And just the opposite.
Therefore, you are accomplishing in manual mode that which Exposure Compensation does in the automatic modes.
Matched movement of both shutter speed and aperture will keep the exposure the same while adjusting depth of field or motion blur.
You can use a gray card to fill the frame and get more accurate meter readings.
Using manual mode allows you more creative freedom, such as adding motion blur, lightening beach/snow scenes, darkening sunsets, compensating for backlight (use the spot meter mode), creating shallow depth of field, etc.
