Darsh, I have no idea what the ProfilePrism metamerism controls do. In PP there is a metamerism slider but I don't know what it really does. Like I wrote earlier this is a very difficult problem and I don't know anyone that has a really good solution.
Hal On Thursday 07 July 2005 06:20 pm, [EMAIL PROTECTED] wrote: > Thanks for the reply . > > >What software are you using? > > I am not using any software .Scanning the IT8 chart using Epson > scanner(no color correction setting) > Getting the RGB values for each patch in the chart,converting it to LAB > by creating a transform between > the scanner profile and dummy LAB profile using lcms library. > But most of the time when my dE goes offlimits ,it is the "A" value in > LAB. > > What kind of settings is ProfilePrism making to counter metamerism?Any > idea? > > Darsh. > > -----Original Message----- > From: Hal V. Engel [mailto:[EMAIL PROTECTED] > Sent: Friday, July 08, 2005 8:32 AM > To: Darshan Pawaskar > Subject: Re: [Lcms-user] printer profiling > > On Thursday 07 July 2005 02:33 am, [EMAIL PROTECTED] wrote: > > I am trying to do printer profiling . > > Normal dE is around 5-6 ,but sometimes it jumps to 15-18 ..and most of > > > > the time for green patches . I am using an Epson scanner which has a > > "florescent light bulb " and not "Light emitting diode ". > > Any algorithms to counter metamerism ? > > Any help will be appreciated . > > This is a very difficult problem because of the number of variables that > are > involved. I never found a way to get good profiles when using a > fluorescent > based scanner with pigment inks (most newer printers are using pigment > inks). > The problem is that every ink has different metamerism characteristics > as > well as different light sources having different metamerism > characteristics > with each ink. So these two things interact with each other in very > complex > ways. The number of possible variations is huge. > > What software are you using? > > I am using ProfilePrism (commercial Windows software) and it does have > some > stuff built in for metamerism. Again I was never able to get this to > work > with my florescent bulb scanner and my pigment based inks even with the > metamerism controls. Others were able to get good results using Epson > scanners like yours and dye ink printers using this software. When I > switched to an LED scanner my profiles improved dramatically. With the > LED > scanner I do not use any of the metamerism controls in ProfilePrism. > > So the only advise I can give you is to minimize the amount of > metamerism at > the source. Unfortunately that means using a different scanner. > > Hal ------------------------------------------------------- This SF.Net email is sponsored by the 'Do More With Dual!' webinar happening July 14 at 8am PDT/11am EDT. We invite you to explore the latest in dual core and dual graphics technology at this free one hour event hosted by HP, AMD, and NVIDIA. To register visit http://www.hp.com/go/dualwebinar _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
