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2005.04.15 03:23 "TIFF Technote 3, draft 2", by Chris Cox
2005.04.15 08:06 "Re: TIFF Technote 3, draft 2", by Andrey Kiselev
2005.04.15 18:44 "Re: TIFF Technote 3, draft 2", by Chris Cox
2005.04.15 19:06 "Re: TIFF Technote 3, draft 2", by Bob Friesenhahn
2005.04.15 19:19 "Re: TIFF Technote 3, draft 2", by Chris Cox
2005.04.26 16:33 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann
2005.04.26 16:56 "Re: TIFF Technote 3, draft 2", by Bob Friesenhahn
2005.04.26 17:26 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann
2005.04.26 18:27 "Re: TIFF Technote 3, draft 2", by Chris Cox
2005.04.26 16:36 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann

2005.04.26 17:26 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann

> The physical units often have no relationship to ideal default "viewing"
> parameters for a computer display.  For RGB data it is useful to know a
> recommended "black point" and "white point" for the image.  It is also useful
> to know the normal range of the data.  The image data is scaled for display so
> that values under the black point are "black" and values over the white point
> are "white".  This is of course only a crude approximation but it is better
> than nothing.

The word 'Alternatively' used by mine was somewhat missleading.

I want suggest an additional information, providing a physical unit for 
all those image values. Maybe gradiation information is needed then as 
well if the image is not linear.

Applications, which dont know how to handle physical units in this 
context, can simply ignore and use instead "black point" and "white 
point", which referes to 'image values used as black' and 'image value 
representing diffuse white'.

Thanks for pointing out.

regards
Kai-Uwe Behrmann
                                + development for color management 
                                + imaging / panoramas
                                + email: ku.b@gmx.de
                                + http://www.behrmann.name