> > Looking at a polaroid (I managed to get one within the last
> > few minutes), I think the usable resolution is way more than
> > 1200 pixles per row (say more than 200 lines per inch).
> I've just realised...
> If you have a 100mm wide print (normal sort of size) and 640 pixels,
> that's only 3 or 6 lpm (depending on whether you think a line is 1 pixel
> or 2). That's not a poor resolution, it's a non-existant resolution!
1 Line == 2 Pixels
Back in the TV time, I've been told that one line equals
a complete black to white cycle or just the maximum possible
frequency (within the visible part of a scan line) where
the signal still reaches top (white) and bottom (black).
To get the same effect on a digitalized display you just
need f(max)*2 pixels - so if an analouge display is capable
of a horizontal resolution of 300 lines, it can display
600 pixels - or it needs a 600 pixel LCD to replace it.
> Ouch!. Now I know why I can't stand those digital cameras.
It's like VHS, DVD, or Windows - simplyfied and just fine
if you look at the average usage - reduced to the minimum
needed quality. For taking a snapshoot and show it to
your aunts - or publish it on your web site (basicly the
same thing ;) these cameras are quite good, since you will
have to reduce the resolution anyway, but while you can get
more aut of a real shot, you can't anhance you digital thing
beyond the starting point (in fact you can't do this with
a real photo either, but the inherent resolution is _way_
bigger than you need).
In fact, this is also why I don't like VHS - maybe good
enough compared to a noisy aired NTSC source, but just
crap, compared to an U-Max or V2000 (I still use V2000
tape machines - still equal to any S-VHS stuff after more
than 10 years of development ...). And of course the same
for DVD vs. Laserdisk.
Gruss
H.
--
Der Kopf ist auch nur ein Auswuchs wie der kleine Zeh.
H.Achternbusch
Received on Thu Jul 15 1999 - 10:38:20 BST