The only reason I do successive compressions is because a) my free PC
software saves images with a fixed compression and b) the free net software
gives a worthwhile space (and download time) saving with acceptable
quality - remember I was talking web publishing, nothing else. That web ref
I gave displays your image with about 10 different levels of compression,
you choose the quality and the space savings. Sometimes the only acceptable
compression doesn't give an worthwhile space saving, so one keeps one's
original image.
PaulH.
----- Original Message -----
From: Max Heim <mvheim@studiolimage.com>
To: MG List <mgs@autox.team.net>
Sent: Wednesday, August 23, 2000 10:40 PM
Subject: Re: Cameras/ sorta MG/ now way OT
> Hmm. As a graphics professional I would not recommend multiple
> compression operations on a single image. Each successive op degrades
> quality in a geometric fashion. Just do your crop and edits, and save it
> once in JPEG format, at an appropriate level of compression. If the
> compressed file size is still too large, go back to the original image
> and save it again with a different compression setting. DO NOT recompress
> the already compressed image, if you give a hoot about image quality.
>
> There is also a phenomenon where the compression artifacts build up to a
> level where they actually add complexity to the image, and further
> attempts at compression achieve diminishing returns.
>
> Of course, I am not referring to "lossless" compression schemes such as
> LZW which is used in the TIFF format, or to ZIP or StuffIt archiving. But
> these do not achieve the high ratios of compression of the JPEG format,
> which is standard on the web. GIF format, which is limited to a 256 color
> palette, is a whole different story. I would not recommend it for
> photographic images under most circumstances.
>
> paul.hunt1@virgin.net had this to say:
>
> >Many if the pictures on my site below ('Bee and Vee', 'Diary of Events')
> >were taken with such a camera - indeed many are digital photos of slides
> >projected onto a screen! (I have a film scanner now). A typical 640x480
> >image generates an image of 70k. When run through my freeware photo
> >manipulation software (GSP PhotoEditor) this reduces to 25k with no
visible
> >degradation in a browser. Further processing with a web compression
utility
> >such as can be found at http://www.netmechanic.com/ can reduce this still
> >further to below 20k. All perfectly adequate for web work.
> >
> >PaulH
> >http://www.mgb-stuff.org.uk
> >
> >----- Original Message -----
> >From: Carl W French <cfrench@cybertours.com>
> >To: <mgs@autox.team.net>
> >Sent: Tuesday, August 22, 2000 10:14 PM
> >Subject: Fwd: Cameras/ sorta MG
> >
> >
> >>
> >> >
> >> >Looking to buy an inexpensive (let me repeat, inexpensive) Digital
camera
> >> >strictly to be used for web sites, the club newsletter, and LBC
> >e-commerce.
> >> >Consumer reports mentions the Agfa e-photo smile as a midrange best
buy.
> >I
> >> >can get one local and the resolution (640-480) is supposed to be fine
for
> >> >the above mentioned uses. Anyone have experiance with sub one hundred
> >> >dollar units? Bud?
> >> >Carl W. French
> >>
> >>
> >
> >
>
>
> --
>
> Max Heim
> '66 MGB GHN3L76149
> If you're near Mountain View, CA,
> it's the red one with the silver bootlid.
>
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