> Phill Heywood wrote: > >> Can anyone offer a reason why after creating a profile (using Eye One pro) >> the printing of the same file on two different types of paper shows >> significant colour differences.
If the colour change is significant!, I'd suggest tracing your steps: After printing out the patches did you wait a day before measuring? If not that's the culprit. Also if the paper has different color initially you WILL see a difference when doing a side by side as a profile doesn't touch the white of the paper, and only gradually (with the Eye One) shifts the balance as the density increase. This will of course also affect the greybalance, especially if one paper is a watercolor art paper, and one is blue white in appearance. Remember usually you'd only see one and your eyes will white balance themselves for each paper. > Michael Harvey wrote: > Here we go... > > The eye one pro is a very good profiling bundle but... as you will note from > the price (~�1000) it has no ability to accept a number of hardware features > that the more expensive (~�8000) spectrolino / spectroscan has available. Mike, most of the hardware features allow the Spectrolino to be suited for more specialised kinds of profiling, like wet offset [polarizer], or materials with optical brighteners (where the software has no provision to handle it) [UV], or measuring stuff for the paint or textiles industry [D65]. > > When building printer profiles, there are a number if issues with paper > brighteners and paper fluorescence which need to be addressed. Indeed. And these can be addresses either in software or hardware. Most frequently though the software handling is superior. Using a UV filter is, according to Bruce Fraser, akin to sticking your fingers in your ears and yell "LA LA LA LA LA", and pretend the problem with optical brighteners doesn't exist. FYI it frequently changes other colours like pure red (erroneously) especially on inkjet inks, and especially if they are prone to illuminant metamerism (or have bad colour stability under different lightsources). > The > Spectrolino / spectroscan has a range of folters available to it (Pol, UV, > D65) which can be used at a number of degree angles for reading the test > patches. For standard ICC profile you should always use a D50/2 degree observer angle. Changing the angle to 10 degrees may be suitable for measuring large areas of coverage (like paint for a wall), but for images it it the only one suitable for profiling as defined in the ICC specifications. It is the only observer angle that corresponds with human vision and images. As you know the human vision functions distinctly different when you exceed a 2 degree viewing angle as the areas of the eye that are thus affected actually have a different colour perception. This effect id built into the calculations. > > Without these options you will never get a 100% purrrfect (:-]) profile for > most media. Even two people using the same spectrolino / spectroscan and the > same software, will often produce two totally different profiles. For RGB profiles I sincerely hope not, not if they know what they are doing and are not just trying all the options for the kick of it <G>. CMYK profiles, however, really require some skill... Best Regards Thomas Holm / Pixl ApS - Photographer & Colour Management Expert - Adobe Certified Training Provider in Photoshop� - Imacon Authorized Scanner Training Facility - Remote Profiling Service (Output ICC profiles) - Seminars speaker and tutor on CM and Digital Imaging etc. - Home Page: www.pixl.dk � Email: th[AT]pixl.dk -- =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
