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Old Aug 14, 2006, 12:19 AM   #1
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I have been experimenting with my SD630 and have found that when I take a picture in manual mode with the flash i can take a picture of an object about 10 to 15 feet away and the picture will come out with the subject well lit. When I take the same picture but zoom in on the subject the picture comes out dark. Isn't the flash still lighting the subject the same? I don't get it, how do I zoom and have the flash work?
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Old Aug 22, 2006, 5:02 PM   #2
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Forany zoom camera the F stop of the lens is smaller when the zoom is greater, when the aperture itself stays the same in terms of millimeters in diameter. Quick example: F/4 for a 50 mm lens is an aperture 12.5 mm in diameter. The same diameter aperture for a 100 mm lens is 1/8'th the focal length which by definintion gives f/8.

The same amount of light from the flash upon the subject, squere foot for square foot, then means less exposure given the different f stop.

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Old Aug 22, 2006, 6:58 PM   #3
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Thank you for the great answer. I think I understand what you are saying. Is there a way that I can compensate for that and change the settings to get better lit zoom pictures?
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