Beginner Trying to Understand QTR
2005-10-20 by John Hollenberg
I finally got around to trying to figure out QTR. Made some pretty good prints without too much difficulty, but having a bit more trouble understanding what is going on with the curves. Some questions I have, in no particular order: 1) What happens if you have first curve selected, second curve is set to "None" and blend is set to 50 instead of 100? Do you get a different result? 2) I noted in the tutorial by Tom Moore that: "Apparently, the Epson printers seem to max out at different places depending on their vintage. The older single dot-size printers (3000, 5x00, 7x00, 9x00) max out around the 50% level. The newer variable dot-size printers (1160, 12x0, 2200, 7600, 9600) can achieve much higher numbers in the 80% to 90% range." However, when I look at the QDIF files for Epson 9600 they all appear to have an ink limit of 50%. Is there something I am missing? 3) When I looked at one of the stock QDIF files, it contains a line which says "GRAPH_CURVE = NO". What does this mean? 4) I notice that the supplied curves are created for 1440. Is there any advantage to using 2880 and creating your own curves? 5) The Sepia curve for Enhanced Matte on Epson 2200 looked only modestly warmer than the Warm curve. I figured it would make more sense to have a stronger curve and then tone it down by blending it with the Warm curve. Perhaps I am doing something wrong? 6) When I click "Create Curve" in the Curve Creator window, I get a window with tabs for both "Linearization" and "Ink Curves". Does the "Linearization" tab show the corrections that need to be applied, or the results AFTER the corrections are applied? Thanks. --John