Friday, January 2, 2009

How I use the light meter

My default setting for automatic cameras is "A-Auto" for aperture preferred automatic exposure. That permits rapid response to unfolding opportunities. When I'm taking my time, however, I use manual exposure and spot-metering.

My Nikon D200 has a 2 degree spot meter setting. For this image (the first of the new year) I metered two locations, as shown by the two circles. The subject was low contrast because of cloud cover. I wanted to place the contrast at the trike about midway between the high and low lights. The darker shadow to the right was to fall where it might. Alternately pointing the meter spot at the two locations, I adjusted the shutter speed (aperture was wide open for that lens to keep ISO low) so that the exposure bar, in the viewfinder, indicated the same distance above and below the midpoint.

This is my simplified version of the Zone System, developed by Ansel Adams and Fred Archer.

For further study, I will be looking into a reputed 12 stop dynamic range for film; compared to the ZS's use of a 10 stop range. Pentax's 1 degree Spot Meter uses 12 stops marked on the dial.

No comments:

Post a Comment

Site Meter