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Old 09-17-2005, 11:30 PM   #3
Cenright
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Join Date: Sep 2003
Location: Beaumont (A town with 25 times fewer people than this site)
Age: 38
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Default RE: What projects are you currently working on?

Project: How inch and footage distances alter the intensity of light, it respects to the photographic unit of a Stop.
Language: For TI-86 Calculator.
Overview:
1 F-Stop difference is double or half of the amount of light getting to the film/printing paper.
F-stop numbers are calculated by:
(Focal Length / Diamater of aperature opening)

In my case, a 50mm lens, so
F-s = 50/Aperture in mm

You figure out the Aperature by using the area of a circle, cutting it in half, and finding the new diameter.
F-stop #1 is a given, and #2, #4,#8, #16, #32 can be extracted from that.
You are working with an area which is squared, and so these are all 2 stops different, not 1.

You can get from any camera or site what the others are, but the problem is that they are estimations.
1.4, 2.8, 5.6, 11, 22

5.6 is actually 5.65...
11 is actually 11.3...
Yadda yadda.

From all this I started to work out an equation, having to use base 2 logarythms and everything. Hopefully when I get my CR1616 Calc Batteries, I'll be able to program it all in and test it.
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