Origins of the Sunny 16 Rule?

[Tin Can]

I was just going to ask in a new post, hows the water temp around the world now.

Chicago cold tap is about 62 degrees F right now and my water heater barely runs.

[Corran]

Lucky you. It's 80F out of the tap here in the deep south, as it is for over half of the year.

[Tin Can]

Yes, but I bet it you seldom have 90% ice on your lakes. We were using ice breakers on our water supply (Lake Michigan) most of the winter and Lake Superior had ice until the end of June.

I prefer cold over hot, we hit 90 today and I never left the cave.

Lucky you. It's 80F out of the tap here in the deep south, as it is for over half of the year.

[jcoldslabs]

Lately I've been having to add ice cubes to the tap water to bring it down to 68°F when mixing one-shot film developer (HC-110 & Rodinal). I think straight out of the tap it runs around 72°F right now. Despite a few hot days our summer here in Portland has been a mild one so far.

Jonathan

[jcoldslabs]

I came across this in a box of old photo stuff. With instructions this complicated, who WOULDN'T want to use the Sunny 16 rule?




Jonathan

[Jim Jones]

Two years after Todd published his Photo-Beacon Exposure Card, my mother was certified to teach 3rd grade. Judging from the textbooks from that time, her students, unencumbered by calculators and light meters, would have had little trouble in using Todd's card.

[Mark Sawyer]

Today's third-graders would pull out their iPhones and check their Sunny Sixteen app...

[Tin Can]

The Photo-Beacon card is very easy with only single digit addition. Maybe today's wiz kids could do it without a phone...

The best thing I ever learned in math, was to do it twice. Once with very round numbers to get in the ballpark and determine decimal place. Then use a slide rule for better resolution.

Two years after Todd published his Photo-Beacon Exposure Card, my mother was certified to teach 3rd grade. Judging from the textbooks from that time, her students, unencumbered by calculators and light meters, would have had little trouble in using Todd's card.

[BrianShaw]

... from about the same era as the Photo-Beacon.

[Harold_4074]

The "sunny sixteen" rule definitely goes back to the 1930s or before; my father used a Kodak book as a text in his Georgia Tech photography course back then, and it covered both the basic rule and the exceptions (light clouds, open one stop; heavy clouds, open two stops, etc.)

He was fond of repeating the instructions that he gave to his Signal Corps photographers: f/8 at 1/250 second, and always use a flashbulb, indoors or out, day or night. And don't mess with the focal plane shutter!

The film was probably something like Super Double-X, and there might have been some pretty heavy negatives, but I know that it is possible to get a print out of a negative that is almost opaque, if you have grade 4 paper on hand and use warm, concentrated Dektol. (Please don't ask me how I know this.... )