JK wrote:
> 
> The thing is, JPEG format always means a loss of quality
> (unless you set the compression level to 0.. I never tried
> that, because it keeps the filesize big, but I think even
> then the quality goes down.

It is true that even 0 compression is not guaranteed not to lose
information under jpeg.  My suggestion is to get the freeware DOS
program cjpeg from www.jpeg.org.  Unlike most converters, it allows
direct access to certain jpeg settings that can help considerably.  Any
setting above about 90% compression is usually a waste of time and
space.  You seldom get any visible difference there.  If you have a
problem image, ofter one with lots of shades of blue and fine details,
use the cjpeg setting "-samples 1x1" when you compress it.  The size
will be a bit larger, but the compressed image will look much better. 
The great majority of images do not need that setting, but if you have a
problem image, try it.  Also, to make your images more jpeg-friendly,
try to avoid large areas of single color with sharp edges.  That is a
sure recipe for artifacting in the compressed image unless you use much
less compression than usual.  Sometimes even then.  Incidentally,
compression numbers between different converters are not comparable.  On
cjpeg, a compression of 90 is minimal compression and high image quality
while some other converters would take 90 to mean extreme compression
and low quality.  Know your tools.

Jerry Anning
cle### [at] dholcom

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