Practical Optics
Monday, December 15th, 2008If you own a camera and like to pretend you can take pictures with it, like me, Derek K. Miller’s Penmachine looks to be an excellent resource for learning how to actually use that very expensive tool.
Esthetics from technology; I love it.
Here’s an excellent sample: using the ISO setting to achieve intermediate f-stop values:
In the old days of film, photographers used to think in terms of two variables: shutter speed and aperture. That’s because the third one, sensitivity or ISO (also known previously as ASA), was fixed for each roll of film. You had an ISO 400 roll, or an ISO 64 roll, or a high-speed ISO 1000 roll, but that was it until you changed the film.
In the digital age, we now have that third variable, because we can adjust the ISO as much as we want, or even have the camera adjust it automatically for changing lighting conditions, so that each picture can use its own ISO setting, as well as its own aperture and shutter speed.