2005.03.21 21:12 "Re: [Tiff] Floating Point Sample Format", by Chris Cox

Those tags aren't supposed to be used for scaling anyway - they're only for information.

(see the TIFF spec)

I did notice the comment in the Spec that the SMINSAMPLEVALUE and SMAXSAMPLEVALUE aren't supposed to be used for scaling. Do you have any idea why that comment is there?

Yes, because that's what the tag means.

It's not a comment, it's a definition.

I have always taken these fields as ok to use for scaling,

And we've found that they're not OK (I tried it once as a solution to some badly written files, and had to back it out because of other badly written files).

but with the caveat that they may not be terrible appropriate. But if we want to avoid a prescanning step it would seem like a good first guess at scaling values.

It's better to scan as you read, or define other metadata for how to present/display the image (because linear scaling usually isn't the best idea).

Chris