[HUG ] Re: IMG: Triptych

Hi Franc,

> I think the point he is trying to make is that when you scan or
> capture if
> you save it in Raw you get what the sensor saw at the time and if
> you save
> it to a tiff, dng or some other format you discard some of the
> data.

Sure, but that is not true with TIFF when talking about a scanner, which is
what I was questioning.

> tiff
> is a lossless format when opened but some of the data (not needed by the
> tiff file format)is stipped off the file before it is saved

Like what data?  If any data is "stripped" that is implementation dependant.
I have a few scanners that save TIFF, and that is THE raw data format for
these scanners.  These TIFFs are typically called "HDR" for High Dynamic
Range.  IOW, they have no setpoints or tonal curves applied...so the image
you see if you were to open the file up in, say, PS, will be typically very
dark...until you apply setpoints and tonal curves to "normalize" it.

> ...so
> the tiff file
> does not contain all the data the sensor saw but a raw file does
> contain all
> the data the sensor saw and nothing else, not even a color space profile.

Well, that's not necessarily true.  At least with the scanners I've designed
and the ones I have.  To save a "raw" file with any of my scanners, you save
it as a TIFF file, with no setpoints or tonal curves set.  TIFF does not
define a "color space profile".

What scanner do you have that saves files as "raw" and it's not HDR or TIFF?

Regards,

Austin


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