Thank you for your response. I will try and clarify my test methods and conditions.
There are two reasons why I don�t believe that post script management is a contributing factor to my test results. The first is that my results are identical when printing through a RIP and when going directly to the printer via the Epson drivers, the second is that the material results that I am getting are identical to the behaviour observable after converting the files into the output profiles in Photoshop and using the info pallet to analyse the test patches. There is no workflow. I create the target files in Adobe 1998 and convert them to the output profil( with no dithering) using the combination of rendering intent and black point compensation I am attempting to test. I usually duplicate the file and convert it prior to printing so that I can write the Lab output values beside the Lab source values and have them print out with the target. When I am testing for the maximum shadow or minimum highlight of a device I make a test file of patches from L*1 to L* 20 against L*0., and L* 90 to L*99 against L*100. Then I simply print the file using post script conversion to the output profile and find the patch that prints the line. Doing this generally produces the following results: 1 Black Point Compensation with perceptive rendering intent is redundant , only the slightest deviations occur, if any, and those usually a long way up the curve. The mapping of L*0 is never different, 2 Black Point Compensation with relative intent usually maps L*0 to a density above the maximum shadow of the output device. If the Printer is using dye inks ( Epson 9600, 5000, 700) then the first line (threshold) usually prints in the second or third when patch using perceptual rendering. Howeverif the printer is using pigmented inks ( 10,000 7,500) the threshold usually occurs much later, often as high as L*14, and despite the use of perceptual rendering and BPC no data below these values is printed. This obviously creates the necessity to manually target the file for the maximum shadow of the output device. Please let me know if there is any other information you require and thank you for your time and interest. Paul Lowry -- >>Paul Lowry >>Academy of Lagado >>Lower Laurentians,Canada >>www.paullowry.com >>[EMAIL PROTECTED] =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
