Re: First camera

On Fri, 17 Apr 2009 10:33:07 +0100, "PDM"
<pdcm99[deletethisbit]@tiscali.co.uk> wrote:
:
: "Alan Browne" <alan.browne@xxxxxxxxxxxxxxxxxxxxx> wrote in message
: news:kKydnSfovZYOJXrUnZ2dnUVZ_v-dnZ2d@xxxxxxxxxxxxxxx
: > Jeff wrote:
: >> Alan Browne wrote:
: >>> Jeff wrote:
: >>>> Alan Browne wrote:
: >>>
: >>>>> Perspective is solely a matter of position and has nothing to do with
: >>>>> lens focal length.
: >>>>
: >>>> Without a long focal length, you can not get distance, assuming the
: >>>> same coverage at the focal plane. It's amazing what a long focal length
: >>>> can do photographing flowers/nature.
: >>>
: >>> Regardless, the perspective from a given position is the same regardless
: >>> of focal length.
: >>
: >> So you would have to crop the image way down if you used a short focal
: >> length. Just what are you arguing?
: >
: > I'm not arguing. Just stating the facts.
:
: Alan is 100% correct. Different lenses are mearly used to change the
: distance where you take the image from.

And who would you define "perspective"? I might define it as "the distance
where you take the image from".

The point is that perspective and focal length are inextricably linked. One is
not the other; but from a practical point of view, one doesn't change without
a corresponding change in the other.

Bob
.

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