In article <4134b858$1@news.povray.org> , Tor Olav Kristensen 
<tor### [at] TOBEREMOVEDhotmailcom>  wrote:

> A camera with 35mm film (36 mm x 24 mm) and a normal lens (50mm)
> will have a field of view of about 40 degrees:
>
> http://www.google.com/search?q=2*atan%2836%2F%282*50%29%29+radians+in+degrees
>
>
> Now I assume that the CCD (or film) in the camera that shot the
> picture that Warp gave a link to, covers the whole field of view
> of the lens.

This is (unless it is a really expensive pro digital camera that you can get
a small new car for) incorrect as CCDs are 1/2" or 3/4", which is much
smaller than film.  This is why you get a tele effect if you use an
inexpensive digital camera with the same lens you used for a film camera.

> I also assume that the image was shot with a 50 mm
> lens and that the image has not been cropped.

A lot of assumptions, aren't this?

> I measured a piece of 35 mm film to be about 0.14 mm thick.

Yes, this pretty much cuts it.

> 6.3 mm / 0.14 mm = 45.3
>
> Now I cannot make myself believe that the internal scattering/
> refraction/reflections in the layers of a such a film will
> extend as far as 45 times the thickness of the film.

Indeed, when overexposing with an extremely bright object like the sun it is
very likely other effects than film scattering will play an important role.
Certainly the lens, but also the atmosphere and even the camera interior
will scatter a real lot of sunlight.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

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