I'm looking for an efficient Windows Lightroom-to-QTR workflow and would appreciate advice from people who have solved the problem I'm having.
Here's the issue in a nutshell: Quadtone RIP uses a straight line color space, whereas Lightroom uses curved color spaces (e.g., Adobe RGB, ProPhotoRGB, Adobe 1998). Straight TIFF exports from Lightroom look fine on screen, but when printed using QTR, shadow detail doesn't match the screen, and prints can look flat and washed out. There’s a good explanation of this issue in Paul Roark's handout called ‘Eboni-4 Plus.pdf’ (http://www.paulroark.com/BW-Info/Eboni-4-Plus.pdf).
As a Photoshop user, the solution Paul recommended in his handout is to work in Gray Gamma 2.2 in Photoshop, and then, for printing purposes only, apply a curve that corrects for Gray Gamma 2.2 to QTR; he provides one called GG22-to-QTR.acv.
In a Windows environment, unlike Mac, you can't print directly from Lightroom to QTR. You have to generate a TIFF, and you can't use Paul's Photoshop curve. One solution is to pull down the dark end of the tone curve a bit in Lightroom before exporting, but that's hit-and-miss, and you end up having to make one version for screen, and one for print. I want to have one version in my Lightroom catalogue that is adjusted at export time for different purposes (like printing with QTR). If you also have Photoshop then the obvious answer is to export from Lightroom, import your exported TIFF into Photoshop and apply Paul's curve... but I don't use Photoshop and I don't want to get it just for this.
My current solution is a bit of a kludge so I'm looking for something better. QTR supplies ICCs for screen and print that provide a straight-line gray space. Lightroom users have to install the RGB version (RGB_Matte_Paper). I've set Lightroom up to export TIFF files using the RGB_Matte_Paper color space, In the resulting exported TIFF files, the shadow areas are squashed down -- but they come back up when printed with QTR.
This works reasonably well... I say "reasonably" because shadows are still a bit too dark in the prints (with important detail sometimes lost). My monitor is calibrated. It's a Dell U2413 and I calibrate with an X-Rite i1 Pro, so I don't think I can blame a too-bright monitor. Other things I've tried are adjusting the QTR profile to lighten shadow detail (e.g., using GRAY_SHADOW=20). That helps a bit, but I wonder if there's a better way. I don't think the answer is to adjust the GRAY_GAMMA value; I don't want to lighten everything -- just the shadows.
Any and all advice welcome -- except "Buy a Mac" ;) I'm printing using Paul Roark's new "Eboni Variable Tone" ink formulation, and I'm trying out his new generic curves (see https://groups.yahoo.com/neo/groups/DigitalBlackandWhiteThePrint/conversations/messages/108825). It's working amazing well on the Premier Art papers I'm using. I just need to resolve this issue and I can focus on making and printing images (rather than fiddling around with QTR profiles).