View lens coverage question?

Mark Baylin wrote:


Does a lenses ability to cover film INCREASE or
DECREASE when it's focused on a subject closer
than infinity (using the same aperture for both
distances)?


Increases. Simplest way to understand it is take some paper and draw a
triangle. The pointed end is the lens. The wide end is the film. The further
the film is from the back of the lens the wider that part of the triangle
gets. If you have the angle of coverage I guess you could work out the math
using that high school geometry I've forgotten.

Nick

"Mark Baylin" wrote in message
...

Does a lenses ability to cover film INCREASE or
DECREASE when it's focused on a subject closer
than infinity (using the same aperture for both
distances)?

Coverage increases when focused closer than infinity. But to get a better
feel for this, it would be best to have a real senario: a given lens and
focusing point, and depth-of-field requisites.