THANKS Sdrummer, good article. I am starting to see / understand how the old 35mm film format terms are being used in Digital.
Now if I understand F-Stops correctly, I want to use the LOWEST ISO possible, like 100, however the lower the ISO, the more light I will need. Is that right ?
All I can remember about 35mm film is that 100 was very good for still subjects and 400 or higher was better for moving objects and bright light (sunlight), I think
With my old 35mm canon camera, I always got 400 speed film and set the camera on automatic
Yes you are correct. With lower ISO's, the sensor is less sensitive to the ambient light, which requires more light to be entered through the lens. And a larger aperture (f-stop), like f/2.8 as apposed to f/8, will let more light enter the lens.
Increase your ISO when you can't hand-hold an image and get a sharp result, or when there isn't enough ambient light for you to get a usable exposure.