Tom,
640x480, 800 x 600 are the number of pixels displayed horizontally and
vertically, so on my 15" diagonal size monitor, this works out in the
order of 70dpi (62 for 640x480, 78 for the higher resolution). Of course
all this is complicated by the no of bits per pixel, which gives the
colour depth  (from 16 to 16.7 million colours.
On checking my cheapie Kodak DC40 digital it gives a resolution of
756x504 with 24 bit colour.
This means  the camera resolution is a good match for the possible
resolution of my pc monitor and video card and is thus perfect for work o
the web.
In contrast, our really expensive JVC digital imaging cameras are
currently being used at a resolution of 1425x1125 but are capable of
higher resolution if you can take the time and handle huge files.

The current resolution equates very roughly to publication quality on an
image about 25% of an A4 page.

So, I suppose that 70 odd dpi with 256-64,000 colours)can be classed as low
resolution which is acceptable for a high percentage of uses and high
resolution is something like 300dpi - 16.7 million colours which gives
slow processing, unwieldy file sizes and a very limited/expensive range of
equipment where the resolution can be viewed.

Hope this helps!

Tim

 On Tue, 30 Jan 1996, Tom
Vaughan wrote:

> So let's see if I've got this right.  The ca. $700 digital cameras are not
> adequate for high quality color print work, enlargements, etc., but at
> least some responders are finding them adequate for on-screen work.  My
> understanding is that most screens are something like 72 dpi; aren't
> "640x480 or 800x600" measures of screen size rather than resolution?
>
> Incidentally, I was astonished to find some very acceptable Web pictures
> are the result of the little throw-away cameras that are not much more than
> a lens and film in a cardboard box.  Again, they wouldn't enlarge worth a
> darn, probably, or be suitable for fine printing, but they look better
> on-screen than a lot of what I've seen on the Web.
>
> Tom V.
>
> Tom Vaughan                    \_   Cultural
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>

Tim

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