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Camera settings

While target acquisition is the fundamental problem, getting the exposure correct isn't simple either. The amount of light reaching the ``film'' depends on the length of the exposure (shutter speed) and the size of the opening (aperture). Most 35 mm cameras have internal light meters to adjust the exposure automatically by selecting the appropriate shutter speed for a given aperture. But to minimize the image blur, which is created by the motion and vibration of the plane while the shutter is open, it is best to use the fastest shutter speed the camera allows, usually 1/1000 or 1/2000th of a second. Thus the exposure must be controlled by choice aperture (F-stop).

If your camera does not automatically vary aperture, the F-stop must be set on the ground before loading the camera in the plane. Setting the aperture on the ground is tricky because the light conditions on the ground are not necessarily the same as in flight. With some cameras it is possible set the camera to "autobracket" the exposure; that is, with each shot the camera actually makes three exposures bracketing the selected aperture.

Give it a try!



Craig Kulesa
Fri Dec 1 16:47:49 MST 2000