i am afraid it will, you just have to move the camera, leaving the lens in place (like, in shift lens). best, mishka
On 1/4/06, John Francis <[EMAIL PROTECTED]> wrote: > On Wed, Jan 04, 2006 at 01:35:50PM -0500, 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 > > No, Bob - it won't, if you consider rotation rather than translation. > > Here's the thought experiment. > > Consider the camera set up (on a tripod) with a 100mm lens, focussed on > a brick wall a little distance away. > > Now apply a small rotation (pan) to the camera, just enough to move the > centre of the image by one brick. The sensor needs to move by the size > of the image of a brick to compensate. > > Replace the 100mm lens with a 50mm lens, and repeat the experiment. The > angular rotation to shift the center of the image remains the same, but > the amount of sensor movement needed to compensate is reduced by half. > > >
