Marcin Gorgolewski wrote:
: For proffesional use: RAW is best (you can always convert RAW into TIFF or
: JPG).
: If you only want to send photos from holidays by e-mail or print 10x15 (you
: don't need more than jpg with 75-97% compression)

I agree with the above. But I have a few slight additions. First most
cameras when using Jpeg then use a "quality" setting instead of a
percentage so the above mention of 75-97% compression would generally fall
in the "best" or whatever the largest quality setting is for that camera
brand.

And since the original OP asked about Tiff, this one was originally
designed as a no-loss compression technique specifically for scanners.
Many photo editing systems include Tiff in their list of compatable
formats. Few if any current cameras use Tiff tho most all do use Jpeg.
And most high end cameras have a "raw" setting but this setting is
specific to the "flavor" of raw from that particular manufacturer.

So I would expand the above descriptions as:
Raw is a camera specific format aimed at professional and "photophile"
individuals (kind of like an audiophile for photography) who are more
involved with precision than in ease of use. (Note, there is absolutely
nothing wrong with this desire.) Also many editing programs will read
(with proper camera specific decoders added) raw images, but few will then
store the results as raw images. So you will need to decide what other
format to use for long term storage. Also you will need some form of
decoder to display or print a stored raw image.

Jpeg is a "lossy" format that compresses the image data greatly so more
images can be stored in the same amount of memory. Depending on the
"quality" seting as to how small the image can be compressed, and inverse
to how much innacuracy of the compressed image when compaired to the
original data. For most casual hobbiest photoraphers, Jpeg is the most
popular format. Many of the people here will be somewhere in the gap
between casual hobbyist and professional and so many long "discussions" of
varying animosity have happened here on this debate. One thing most of us
can agree on, each time a jpeg image is recompressed (opened, maybe
edited, and resaved) additional innaccuracies will be introduced, so if
you wish to use Jpeg for the camera, and then jpeg for long term storage
so that storage is maximized, all operations inbetween (such as repeted
editing and resave operations) should use some non-lossy storage such as
Tiff, or the adobe format, so that no further inaccuracys in the data will
be added when not necissary.

Tiff files are somewhere inbetween raw and jpeg for storage size (in
general) and some newer versions seem to have a quality setting similar to
jpeg that could make it lossy like jpeg when anything less than 100% is
used. This is a good mid-edit storage format. Personally I don't use this
for long term storage.

Hope this expansion of descriptions is helpful.

Randy

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Randy Berbaum
Champaign, IL