P3D List of empirical exposure settings

[fj834@xxxxxxxxxxxxxxxxxxxxx (Dr. George A. Themelis)]

The so called "Harris Photoguide", available from PO Drawer B, Rochester NY
14617 (not sure if it is still available) is like an exposure meter
calculator.  Inside it lists the following:

-1  Bright sunlight on snow or light sand
 0  Bright sunlight with distinct shadows (front lighting)
+1  Hazy sun with soft shadows
+2  Cloudy bright w/no shadows. Sunset w/sun visible.  Moon
+3  Heavy overcast. Bright shade. Last 5 minutes before sunset
+4  Dark shade. Twilight at sunset
+5  Tree shade
+6  North window light, forest shade, carbon-arc acts...
+7  Brightly illuminated offices, store windows, etc.
+8  Minimum illuminated offices, lighted city streets...
+9  Bright home interiors at night...
+10 Average home interiors at night
+11 Candlelit close-ups
....
+18 Full moonlit average landscapes

The zero point is f16 @ 1/ASA "sunny day"

What amazes me is that typical lighting conditions are very constant. For
example, office illumination usually varies within one f-stop.  As I
recall, all my metered office pictures (inside different offices) have been
between f8 and f11 @ 1 sec. (+7 to +8 with ASA 100 that I use)

Why would anyone would want to memorize these settings instead of just
using their trusted meter?  Among other reasons, because the meter is
useless if it is missing from the camera bag.

This table also explains why pictures taken inside houses in the night with
bright lights on but no flash are usually very dark (+9) or why if you try
to estimate how much light there is in a forest you usually get
underexposed pictures (+6, but it does feel brighter!)

-- George Themelis


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