Re: [OT] Lenses [Was: [OT] Cameras again]

In article <4c2fffe04d%Graeme@xxxxxxxxxxxxxxxxxxxx>, Graeme Wall
<Graeme@xxxxxxxxxxxxxxxxxxxx> wrote:


> At 35mm (50mm on a 35mm film camera) the perspective of the view is very
> similar to the human eye. Shorter focal lengths expand the perspective
> introducing increasing distortion until you eventually get the fisheye
> effect. Longer focal lengths compress the perspective.

Just for the fun of arguing, and from a little bit of 'satiable
curtiosity'[1], how can you tell?

Human eyes don't have a flat plane of film at a fixed distance from the
optical centre of the lens. In fact they act like a view camera with a
maniac in charge of the swings and tilts and lifts. Furthermore,
depending on what you are looking at, they appear to switch off more or
less of the retina (CCD) when it suits. Compare looking into the far
distance to see if that is legs walking off the footpath as seen under
a car parked 200m ahead, and catching sight in the side mirror of the
glove of a biker about to do a loony mezzanine lane stunt behind you.
In 35mm terms, that's a 18-500mm zoom in less than 0.2 sec.

How can you possibly determine a field of view?

1. Can you tell I've been reading a Just So Story to a grandchild
recently? (O Best Beloved)

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Relevant Pages

  • Re: [OT] Lenses [Was: [OT] Cameras again]
    ... > In article, Graeme Wall ... >> similar to the human eye. ... Longer focal lengths compress the perspective. ... the retina is at a fixed distance form the optical centre of the ...
    (uk.comp.sys.mac)
  • Re: [OT] Lenses [Was: [OT] Cameras again]
    ... >>> similar to the human eye. ... Longer focal lengths compress the perspective. ... >> optical centre of the lens. ... the retina is at a fixed distance form the optical centre of the ...
    (uk.comp.sys.mac)
  • Re: [OT] Lenses [Was: [OT] Cameras again]
    ... >> range for a CCD. ... > ISTR reading that 35mm typically gives a field of view similar to ... similar to the human eye. ... Shorter focal lengths expand the perspective ...
    (uk.comp.sys.mac)