Sunny 16 teaches you the difference between full sun and hazy. Hazy and cloudy. Cloudy and overcast. I'm going to bet it wasn't really full sun. What did the shadows look like?
On the point about the ASA change. Download this:
The exposure suggestions are Sunny 16. Last I checked Japan is pretty far north to. I don't know if Ilford still provides little inserts with exposure suggestions but if they do I bet it's Sunny 16 to. last I checked Agfa used Sunny 16 in it's box inserts.
Sunny 16 isn't intended to be used with the box speed but with the film speed that works best with your system. If you wouldn't set the box speed on an exposure meter then why would you use it with Sunny 16?
The definitive research was done by Loyd Jones and his team at Kodak in the 1930s and 1940s. the seminal paper on the subject of illuminance of daylight is Sunlight and Skylight as Determinants of Photographic Exposure. I. Luminous Density as Determined by Solar Altitude and Atmospheric Conditions. and II. Scene Structure, Directional Index, Photographic efficiency of Daylight, Safety Factors, and Evaluation of Camera Exposure, JOSA, vol 38 and 39, Feb 1948 and Feb 1948.
The mind numbing seventy or so page paper was so thorough that it was made into the ANSI exposure guide, ANSI PH2.7 - 1986. It is said that if a meter disagrees with the guide, the meter is most likely wrong. It may be a coincidence, but the first ANSI light meter standard and transparency speed standard came out at the same time as Jones paper, and Jones was on the ANSI committee on exposure meters.
The light meter has to determine three different film types (transparency, color neg, and b&w neg) using the same meter reading. All three are determined differently. The meter can only be precise with one film type and it has to assume the other two. Since exposure is most important with transparency, the exposure meter is geared specifically for the transparency. The meters indicated exposure was the same as the transparencies speed point. In recent years, there has been a small adjustment in transparency film speed.
A good question about Sunny 16 is what is defined as sunny - how many clouds, what solar altitude, what latitude, what altitude, etc?
Exposure is based on 10,200 footcandles with the meter pointed directly toward the sun or 7680 footcandles when the sun is at an approximate angle of between 40 to 45 degrees. The light reflecting off a middle gray card when the sun is at a solar angle of 40 to 45 degrees is 933 footcandles. At f/16 the light striking the film is ~ 2.4 footcandles at one second. With an ISO 125 film, the shutter is set to 1/125 and the amount of exposure is 0.0189 footcandles or (~ 0.064 meter candle seconds).
I'm not sure I am following that. Are you saying that 100 asa b&w print film has a different speed than 100 asa transparency? or that transparency is best when it is under-exposed. If that is the case, why isn't a 100 asa transparency rated 80 asa? Or have I completely missed the point?... a very likely possibility
Originally Posted by Stephen Benskin
To me this discussion goes back several days to a post that sugested something like a wannabe photographer should learn to see or read available light to make good exposures without a meter. This is possible and has worked well for me for over fifty years, the missing link is that folks that use the "Sunny f16" rule often do not learn to really see what is necessary to make it work. One must learn to interpret the shadow regardless of how high or low the sun (main light) might be. I don't intend to give you any short cuts in learning to see light or read shadow because I don't think there are any. I believe only experience can teach this. What is bright sun light? ask that question and most likely you will get several answers. For my self on a bright sunny day I look into the shadow, fence post, telephone pole, tree,
side of a building or the triangle shadow right under a persons chin. Makes no difference, the shadow will tell you its story. You will see absolutely no detail in a shadow cast on a truly bright sunny day. I f you can see detail in the shadow it is not being cast by a bright sun, clouds, atmosphere, dust or whatever is diffusing the sun. The more detail you can see in the shadow the
less bright is the sun. That simple! Kodak's rule will work today if you use it
properly. Look at the subject determine if you can see detail and how much, or is the shadow soot black. If there is no detail, you'll have to modify your exposure to achieve the image you want. The zone system addrersses this.
Part of the Kodak rule says: Expose with the sun directly behind or over the shoulder in front light, If the sun is lighting your subject from the side, give a half stop to a stop additional exposure. If backlighted give a stop and a half to two stops additional exposure. Rule of thumb has been challenged in this thread, but most rules of thumb I have found, were based on proven fact.
These old wives tales when properly interpreted and executed can give you excellent results. I learned to see and understand light and shadows in a time when exposure meters did not exist. Photography was all seat of the pants, even Ed Weston did not use a meter until much later in his photography. Today I see no reason to own a meter and not use it. Few
meters get it right every time, you have to learn to interpret the meter and when to overide it. The gray cards I use do read 18% reflectance gray, somehow I have it in my mind that if it reads 12% it isn't an 18% gray card.
regardless correct exposure can still be interpreted from it with a few adjustments.
Making good negatives can be made without all falderah and fiddle faddle. There is in my mind no short cuts, simple hard work will get you the experience to make good exposures under any lighting circumstance.
Available Dark, has caused me many problems in my life however.
Not sure of the answer, but isn't Sunny f/16 what most of the disposable cameras are based on? Note: there is no one rule (or whatever you want to call it) that will fit any situation..however with a little thought put into it, Sunny f/16 does work as a good guide.
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
But why bother- using a meter doesn't take much, if any more time than assessing all the factors to use Sunny 16 optimally and measurement is going to be more accurate than a guided guess whenever exposure is in doubt or critical . In any case I don't think you can expose transparencies well consistently by making a single assessment, no matter how derived- whether a meter reading or a guided guess.
"Make (extensive) notes for each exposure and analyse each print, negative or chrome"
This just isn't what I want to do when I'm photographing. I want to concentrate on composition, decide where I'm going to move next; judge how I want my photographs to look; assess whether this shot is going to improve if I wait, and so on - not write stuff down for close examination later on every shot. I can do this only if I have a process for assessing exposure that works materially all the time. Sunny 16 wouldn't do it for me.
Most of you don't know this but my real occupation is in the top secret US Government Department of Spaceology. Several years ago we made the alarming discovery that the sun is going out. Up until now, to avoid panic, we have been trying to cover this up by distracting the public with the bogus myth of Global Warming. Our Black Ops division introduced and popularized the digital camera so that no one would notice that the sun was steadily becoming dimmer.
Now the Cat is out of the bag. Darn you analog photographers and your cursed Sunny 16 rule!
That is called grain. It is supposed to be there.
Stephen, I have to ask this... How long did it take you to dig up this reference?
Originally Posted by Stephen Benskin
(BTW - this was not making fun or taking a cheap shot)
Some people are like Slinkies. They're really good for nothing, but they still bring a smile to your face when you push them down a flight of stairs.
The speeds of the different materials are determined at different points of their curves. While B&W film film speed is determined at a point in its shadows, transparency film is determined in the middle of its curve. The reason why they have the same ISO, is because of their speed equations are different. It's the beauty of photography that they were able to tie all of this together and make it work most of the time.
Originally Posted by SchwinnParamount
B&W - 0.8 / Hm - Hm = exposure at a density of 0.10 over fb+f
Trans - 10 / Hm - Hm = exposure at film mean - mid point
An good equation to illustrate Sunny 16 is the exposure meter balanced calibration equation.
A^2 / T = (B * S) / K
A = f/stop
T = Shutter speed
B = luminance in footlamberts - average is 297
S = film speed
K = constant = 1.16
Plugging in Sunny 16 for a 125 speed film:
16^2 / 1/125 = (297 * 125) / 1.16
1/125 and 125 cancel out leaving
256 = 297 / 1.16
297/1.16 = 256
256 = 256