Hi Russel, On Tue, 21 Mar 2006 14:15:41 -0700, Russell Kerstetter wrote:
>I mostly lurk here, however I do have a question that I have had >answered is two different ways, and always by someone who knows more >than me. > >The Pentax dslr's have a 1.5 crop factor, so this means either: > >1) A 50mm focal length is still a normal perspective only with the >sides cut off, because the sensor is smaller than a 35mm negative, and >so the recorded image is simply smaller because of that. Correct, perspective does not change ... >....or.... > >2) A 50mm focal length is now a medium telephoto perspective, with the >same effects, with regard to image compression (from front to back) >and depth of field, in the same way that on a large format camera a >50mm focal length is a wide perspective. Well, this may the effect you are observing, but that is not caused by the 'crop-factor' or 'tele-factor' at all. A 50mm is a 50mm, no matter on what camera you are using it ... The perceived change is caused by YOU, changing your position to keep roughly the same subject in view :-) Perspective depends on STANDPOINT only. On that given standpoint, the lens-focal length, and the size of the image-area (film or sensor) determines how much of the subject will be in view. (aka 'field of view') >I feel like there is some concept about the mechanics of a lens that I >do not understand, but both explanations make sense to me, so I don't >know. :-) Regards, JvW ------------------------------------------------------------------ Jan van Wijk; http://www.dfsee.com/gallery
