If the lens/body was moved in a perfect parallel manner, then you are
right, 1mm of body/lens movement == 1mm of subject movement. If you
deviate from the parallel motion, then there is a magnification involved
which includes the angle of the motion as well as the field of view of
the lens. With long lenses, the FOV is very small, therefor any small
andular movement seems highly magnified.
rg
Bob Shell wrote:
On Jan 4, 2006, at 9:11 AM, Steve Jolly wrote:
A 1mm shift of the camera will only produce a 1mm shift of the image
on the sensor if the lens is at 1:1 magnification. That's not true
in the general case. Lenses magnify. Different focal lengths
magnify by different amounts. This applies to image shifts just as
it does to the images themselves.
I still do not think this is correct. A point projected on the sensor
by any lens will move 1mm if the camera body moves 1mm. (Equivalent to
moving the sensor 1mm).
Bob
--
Someone handed me a picture and said, "This is a picture of me when I
was younger." Every picture of you is when you were younger. "...Here's
a picture of me when I'm older." Where'd you get that camera man?
- Mitch Hedberg
