[WEB4LIB] Re: E: Sort of an easy question - how to write a page that

[Edward Wigg]

At 07:37 AM 2/27/2001 -0800, Walt_Crawford at notes.rlg.org wrote:
>....
>2. On the other hand, you really can't _safely_ use anything but the
>200-odd Net-safe colors. Why would a business user have a PC set to use
>24-bit color? 16-bit color--and, for most business use, even 8-bit
>color--lowers overhead and typically allows higher refresh rates.
>....

This isn't quite colors work -- the Web-safe colors are only used for
blocks of color that you don't want mangled or dithered in some
unpredictable way across different platforms when either used as
backgrounds or used in the sorts of images and graphics that are best
represented as gifs. For photographic and similar images (the ones best
displayed as jpegs) you want an adaptive palette, preferably with no
dithering (hence high bit depth). For examples of why you do want the
Web-safe colors for graphics and don't want them for photos see Lynda
Weinman's "Browser-Safe Color Palette" page
<http://www.lynda.com/hex.html>. (For an even more in depth look at why
those particular 216 colors are, or are not, "safe" look at "Death of the
Websafe Color Palette?"
<http://hotwired.lycos.com/webmonkey/00/37/index2a.html?tw=design>.)


For "most business use" 256 grays are definitely adequate (nice operating
systems even allow you to choose this option if you want it), but as most
new PCs come with fast processors and _very_ capable graphics cards (the
$1200 Dell Dimension 4100 comes with a 1GHz PIII and a 32MB DDR NVIDIA
GeForce2 GTS AGP), it seems silly to worry too much about refresh rates. As
with monitors and resolution we should design sites to be _usable_ at low
bit depths, but it is foolish to arbitrarily assume a limit of 8 bit color
except in special cases.

Edward