"Gerhard Fürnkranz" wrote:
Graeme, I guess it is rather not like absolute colorimetric in the traditional sense, but more like "ICC absolute", i.e. a perceptual transformation which basically maps the PCS gray axis [0,0,0]...[100,0,0] to a gray axis with illuminant chromaticity (not paper chromaticity), while scaling down the luminance (from 100 to paper white) and possibly bending the gray axis towards paper white at the top in order to avoid the otherwise inevitable clipping.
Hi Gerhard, Given that D50 is a constant assumption in ICC, then I guess this effectively translates to an assumption of a spectrally flat reflective media ? [ie. a media that has a D50 white point when illuminated with D50.] But the reality is that the observer has no in built neutral reference, and adapts to the viewing situation, so I'm not clear on the circumstances in which rendering as if in an absolute colorimetric mode with the source being a spectrally flat media, gives a visually desirable looking neutral. If the output media has a cool white point itself (ie. lots of FWA), then the neutrals would look too warm. If they don't look too warm, then the observer must be adapted to something other than the output media. What are they assumed to be adapted to ? cheers, Graeme.