Archived from groups: rec.photo.digital (
More info?)
imbsysop <imbsysop@yahoo.com> writes:
> On 15 Dec 2004 20:45:00 +0800, Bruce Murphy <pack-news@rattus.net>
> wrote:
>
> >imbsysop <imbsysop@yahoo.com> writes:
> >
> >> On 15 Dec 2004 19:54:15 +0800, Bruce Murphy <pack-news@rattus.net>
> >> wrote:
> >>
> >> >"Ryadia" <ryadia@hotmail.com> writes:
> >> >
> >> >> Perhaps Bruce, you could enlighten us as to the definition?
> >> >
> >> >A discrete element of a planar space, usually rectangular. This isn't
> >> >complicated.
> >>
> >> you mean that's the definition of a sensel on a sensor ?
> >
> >No, I don't. A pixel is an abstract concept for which there are many
> >physical realisations with varying levels of divergence from this
> >original definition..
>
> so why not stay with the original definition ?
Because the 'original' definition is not only fairly naive, but has
also become corrupted by decades of near-enough approximations.
Nothing I've said above makes them any more useful.
> It is simple enough
> to cover the general idea of being a picture element ..
But you need the word discrete there. You also need to point out that it
is planar, not volumetric.
> (and hence
> have no dimension
And where did 'have no dimension' come from? Why should a pixel not
have an extent, and thus dimensions?
>
causing the eternal confusion between the pixel
> itself and its representation on any "picturing" device)
This 'eternal confusion' is really just stupidity on the part of
people frightened of simple multiplicative relationships.
> Now it has been smeared out from being a sensor (sensel) in a Bayer
> pattern CCD up to "I_don't_know_what" ... obscuring all & everything
sensor elements, particularly ones in a Bayer map sensor don't map
directly to pixels in the final image, which is presumably why this
other ridiculous term emerged. In a monochrome sensor, or in something
like a foveon, they do map directly.
B>