Originally posted by pacerr Perusing this thread, it seems apparent there's still room for further explanation of the "Sunny 16" thing -- at least for some of the newer folks.
"Sunny 16" doesn't just apply to the use of f16 on bright sunny days. It's merely a memory aid for a process which may be used as a starting point for calculating ANY exposure value for ANY reasonable lighting condition and ANY type of photography gear.
The exposure table that accompanied most films looked something like this:
Given ISO/ASA value = nearest shutter speed
Snow/Beach - very bright, glare = f22
Bright sun - crisp shadows = f16
Hazy sun - indistinct shadows = f11
Cloudy - no discernible shadow = f8
Open shade - no direct lighting = f5.6-4
Using the reciprocal values for EV, the aperture or shutter speed may be selected to suit ANY aperture/shutter speed combination. E.g., (assuming ISO 200), f 16@1/250 could just as well be f8@1/1000 or f32@1/60 depending on the speed and aperture values desired.
Likewise, the exposure value may be adjusted up or down to suite the lighting conditions.
But shutter speed and aperture were expected to be adjusted according to the reciprocity rules to suit the photographer's intent (i.e., blur vs. DoF) and equipment limitations.
As stated earlier, ISO (ASA) didn't necessarily match the shutter speeds available and these ballpark values still benefited from minor adjustments based on personal experience with one's camera, film type and processing methods and using EV adjustments for equipment quirks and processing methods were the mark of experienced photographers. Where inexperience or uncertainty was involved it was suggested that bracketing be used.
These suggestions are still found in every basic photo course and in the mental tool box of most older photographers and work as well today as 100 years ago.
( It's also worth keeping in mind that when this "rule" was developed an "advanced" camera might have only had one or two choices for both aperture and shutter speed. Sometime they were linked and merely labeled "Sunny", "Cloudy" and "Bulb"! "Bulb" was manipulated by a pneumatic tube attached to a squeeze bulb and speed was timed by counting aloud, "One Mississippi, Two Mississippi, three . . . ah, the good old days were so simple, eh? )
With the availability of instant digital review with "blinkies and histograms" in modern digital cameras there's little excuse for badly missed exposures today even when using the "Sunny-estimate" rule in lieu of TTL metering.
Properly using a light meter, whether hand held or TTL, requires more skill and experience than most persons realize -- as demonstrated by the continuing saga of poorly exposed images and condemnation of metering technology.
H2
Bingo.
Also, it's to bear in mind that most films of the day had more overexposure latitude than even the best digitals of today. It'd still be a good rule-of-thumb for *proper* exposure, but don't ever think the world never gets brighter than 'Sunny 16.'
Long time no see, btw, Pacerr, and good to see you. Are you still dealing in Mamiya stuff?