On Jan 5, 2018, at 1:15 PM, Ben Goren <ben@trumpetpower.com> wrote:
On Jan 5, 2018, at 10:52 AM, forums@walkerblackwell.com wrote:
I guess my question is, has anyone found a scientifically consistent way to get around this “appearance” match and simply set the output conditions for linear?
"Linear" by what measure? Ink coverage? Total reflectivity? L*?
L* yes. (Only thinking about the neutral and near neutral axis so completely in-gamut).
What's your viewing environment like?
For the sake of this exercise, the viewing environment is the conditions inside of the spectro. Just dMax to dMin (related to tile white) is the only considerations as far as environment is considered. The viewer is the spectro.
If you set the print in that splash of sunlight coming through the window, will you be upset that even the black patch of the print is brighter than the monitor's white?
Typically, linearization is something done before profiling, and as a means of improving the consistency and applicability of profiles.
Yes. I’m talking about linearization as a ink on paper destination not of a target tiff file.
As in, linearize printer serial number #3141 and profile BrandName Premiere Photo Matte paper, and the profile should be equally valid for any printer of the same model with that paper paper after it's also been linearized. The measure for linearization doesn't matter so long as it's consistent, doesn't have inversions / discontinuities, and so on. I imagine most manufacturers that implement this feature use total reflectivity. ArgyllCMS has a function I've never personally needed to do something similar with printers that don't support in-printer or in-driver linearization.
It would probably also be useful to ask _why_ you want "linear" output.
Linear output allows for 100% consistent movement of shadows and highlights in Photoshop. Aka, any input or output shadow changes in a photoshop curve will act the same way as the highlights. When an ICC that does appearance matching is involved, shadow movements are minimized relative to the shadow compression (and can also be de-stabalized related to RelCol) making shadow adjustments to the image unstable and not consistent. I say this as the maintainer and current builder of Piezography which is a linear print output workflow that has been going for about 2 decades now. I’m wondering about how this can be applied to color ink workflows, not just b&w with ink curves.
The most common closely-related scenario I can think of would be to send "raw" data to the printer as the first step in creating a profile. "Print without color management" would be the typical phrase...and it can be a real bear, sometimes, to make that happen. The least unreliable and most universal approach is the so-called "null transform" hack: assign the image to a particular profile (doesn't matter) and use that exact same profile for the printer profile. Worst case, if the CMS is even remotely sane, you might get some floating-point rounding going on, but simply breathing on the print will change the color appearance by more than that rounding will.
Yes. RGB-Space to RGB-Space (null transform). I’m talking about an actual ICC that is created after the fact that prints linear for any given gamma (lets say AdobeRGB/Gamma2.2 for sake of the discussion.) and does work for a given paper/printer/ink. Cheer! Walker
Cheers,
b&