Datacolor User to User Support Group.

--- In colorvision_group@yahoogroups.com, randy <rlphoto@...> wrote:
>
> Hello everyone,  I can handle a little color shift here and there. I do 
> 90% custom portraits for a living and the rest editorial, so exact
color 
> is not necessary. As long as it is close and looks good.  The skin
tones 
> are the most important of anything. I was very impressed with PFP skin 
> tones so far.  It was also able to correct the green blocking shadow 
> problem of the actkinson profile that I was having also.  But I cant 
> deal with the posterization that occurs along with the color shift. And 
> sometimes the color shift is pretty severe.  And if doctor pro only
uses 
> PS tools for correction I cant see this as a global solution either.  
> The actkinson profile doesn't have this problem, so I know it is 
> correctable.  I believe like Xun, that  the problem lies in the 
> algorithm.  But all I ask for is a solution. If I am at fault is some 
> way, please help me correct it so I can go on using this product and 
> making a living.  If this issue is not correctable,  then let me
know so 
> I wont spend anymore time looking for one.
> 
> Thanks and have a good day.
> 
> Randy Laskody

What if collectively we come up with a somewhat harsher test image. 
One that stresses the portions where we are finding issues like
posterization and blue/purple color shifts?  It may be interesting to
keep it photographic, not mathematical like a Granger Rainbow.

I'd like to have a use it for the following to test how well a profile
works (in gamut colors) and how well the CMM engine works (out of
gamut colors) while making clear which component is responsible for
each.  It would also be interesting if it had gradients which stressed
the areas where 8bit images show posterization and 16bit images do
not.  I realize that this test is a bit unfair but ... if we keep it
photographic ... its definately real world and exercises the real
world issues we face.

What do you think?  Is this just beating a dead horse because it has
been done already?  How about the center containing colors which are
normaly in gamut while the outside contains colors which stress the
CMM engine?

Its just an idea ... feel free to stomp on it .. shoot holes in it
etc.  Thats the only way it really gets better :-)

Thanks

Tom