🚀 go-pugleaf

In article <1992Dec22.140602.11165@ircam.fr>, francis@ircam.fr (Joseph Francis) writes:
> In article <1992Dec22.004028.1@cc.curtin.edu.au> zrepachol@cc.curtin.edu.au writes:
>>In article <1992Dec17.161309.10151@ircam.fr>, francis@ircam.fr (Joseph Francis) writes:
...
> Why 300dpi? Everything I've read says that the eye, in normal
> conditions 29.7 cm from a 21x21cm square (the correct distance for
> looking at photographs, w.r.t. the image size for least optical
> distortion), can't resolve more than 300dpi @ 256 grey levels per
> pixel of the image. I think it has to do with the angle subtended by
> the image on the retina, and the density of receptors. Color is
> similar in treatment, 300dpi per color layer, but this model doesn't
> account for discrepancies in color sensitivity (green, vs. red).
> 

I've seen this bull too. Need I say more? The problem is that a simplistic
'resolution required' test fails in many subtle important cases, where the
resolution errors compound in horrid ways. That is why good typesetters run
~7k dots per inch or more.

Knuth, in one of the TeX/Metafont books/srticle gives a sobering example of
round-off error in the 13 odd decimal place. Can't find the ref at the mo...
In the article on device drivers I think.

The Kodak leaflets on screening have a lot of good stuff on this ( or at least
they used to, I haven't looked at onne for 20 odd years... )

~Paul