Datacolor User to User Support Group.

Like David said to you, you must check with real life images an not just with Gamut clipping. While I also like the gamut clipping method, you must be very careful about how you interpret it.

Usually when you profile for a matte paper you need to ADD some Shadow detail. My favorite value is +4 or +5. The profiling software always tries to get the maximum level of contrast (perceptually) for a profile, while trying to maintain maximum accuracy for colors and tones. i.e. to get the best "punch" with your images. But it may happen that the default values used by the software are not necessary the best one for a specific media. It is why we can control some parameters inside S3print to create our profiles and tune it to our taste. For me it is more important to have a good control in dark tones. I prefer to get 2% less contrast and still see details in the shadow. But it's me. Others may not like it this way.

No profile generation algorithm is perfect. There is always compromise to do and the laws of physics are the same for all software developers. 100% perfect profiles without human intervention (and even with it) are not possible to achieve.  Color models also have their limit (and some internal flaws), which restricts the maximum result achievable.

S3Print give you a lot of accuracy and quality for the price you pay. Good luck to find better software in this price range (and even if you look at the far more expensive ones)

The software must work with a very wide range of papers and medias. Default values may work better on medias showing a wider gamut like semi-gloss or luster photo paper. But they also works well with matte medias. I'm running a Fine Art printing business and consequently I mostly print on matte papers and I still have to find someone able to build better profile than what I can do with S3print on any matte medias.

Now, It is about 99% sure that by using negatives value on the shadow details sliders you will clog your shadows. But you will add more ink in the dark areas and maybe you will get a better black, and that the gamut clipping is reduced near pure black tones.

But I suspect that in practice, if you print with these "dark tones boosted" profiles, you will not see any difference in dmax (pure black) and you will LOSE details in the shadows.

Beware that it may be subject related. So if you try it on some pictures, use many different pictures to test. For this specific case, try to print a model with some dark hairs, or peoples wearing dark clothes, and see what you like the most.

Matte papers are not so easy to use and while some photographers and artists like it a lot and give high credit to these products, it is clear for me that it is not with it that you will get the widest color gamut. You will have to use these papers when you need a 100% matte finish or if you want to replicate the natural finish of a watercolor paintings, or if you like the look, or if you find that your Fine Art pictures produce an interesting "feeling" when printed on it etc. These are not product to achieve the widest color gamut prints. You will have no choice to play with hardcopies and experiment on many pictures using different sliders values.
My own recipe on Hahnies matte paper with K3 ink is:

Brightness set to -2
Saturation set to -2,
Yellow/blue slider set to +6
Shadow detail set to +4. 

To get these values I used hard copies and a lot of soft proofs. I also check the gamut clipping info but usually the soft proof on test images is the best to find the best adj values.

Good luck!



> On intial viewing of a hard print of the test image with a Shadow adjustment of -10% I can see the image seems to have more contrast in a nice way although possibly it needs some minor adjustments by a few % to get close to the original image...
> 
> Rgds
> Rick

> > Daniel Vézina
> > Technical Director
> > Numart Inc. 
> > QC, Canada
> >
>