PDN and QTR, blowing out highlights
2011-12-29 by Harlan Chapman
Hello Ted, Have a look at this thread if you are on a Mac. It describes a printing issue that can lead to blown highlights in your prints depending on your workflow: http://tech.groups.yahoo.com/group/QuadtoneRIP/message/9205 The following image shows measurement of LAB luminosity of a step wedge in gray gamma 1.8. The red line was printed from CS3, it shows the proper linear values. The blue line shows it printed using CS5 and demonstrates the shadow values blocking up due to the glitch Roy describes above. You can't linearize this out by tweaking profiles or adjustment curves, your negative will always print too dark in the shadows to blow out the highlights in your print. http://img225.imageshack.us/img225/1936/cs3vscs5.jpg The workaround I use is, in CS5, to work on my images in the "generic gray gamma 2.2" space. That way Photoshop doesn't change things when you print. I use CCII to generate my adjustment curves for my QTR profiles. Works great. Can do it manually but CCII is cleaner and it is also easier to tweak the curves while in CCII instead of on the Photoshop curve window. Best of luck to you, -Harlan [Non-text portions of this message have been removed]