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Old 11th April, 2005, 08:55 PM
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Originally Posted by danrok
A small depth of field will put the background out of focus. So, you might use a small aperture in good light just for this effect. If you want everything in focus you may need to use a larger aperture.
Tsk, tsk You need a small aperture (bigger F Number) for greater depth of field

Only thing I'd add is that the camera's built in light meter will make a pretty good job of estimating what the shutter speed and aperture should be to give the correct exposure. The meter is designed to assume that any given scene will have an average light reflectance of 18%. Most cameras by default take the reading from around the central part of the image, it’s known as “centre weighted”. More advanced models give whats known as multi segment (from a number of different parts of the shot) or spot metering which can be as little as 1% of the image.

Because of that very bright scenes or very dark scenes can fool the meter. If it’s very bright the camera will assume that less light is needed so you actually need to ADD to the cameras calculated exposure. For example let’s say you’re taking a photo of a light bulb which is on. The camera might say F8 and 1/500th of a second. Because it is being fooled by the bright light you may need to reduce the shutter speed to say 1/250th to get enough light in to get the correct exposure.
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Last edited by dod; 12th April, 2005 at 11:07 AM.
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