QTR-Quadtone RIP

--- In QuadtoneRIP@yahoogroups.com, "steveoshoots" <steveoconnell@...> wrote:

> I am trying to get some glop (epsonGO) to print through QTR. I'm running QTRv2.6.2 on Mac 10.5.7. printing with an Epson R1900. The inkset is UT3D parts, too long of a story :( . I have a good warm curve, LC and C mixed in the toner section, LK and PK mixed in the gray. And I have a good cool curve, LM and M in the toner with LK and PK in the gray. I combine these in the QTRprint dialog curve mix and love the results so far... 
> Is there some code line or something added in the quad curve creation that will pour on the glop without trying to undercut the inks?

Hello Steve, here is a method that will work with OS X and the GLOP (or any other channel).  After the toner lines add the line:

CURVE_GL=

There are now two ways to define the curve. 

1) insert points in the following format:  <open quote><input @ white point><semi-colon><channel output><single space><next input><semi-colon><output><single space> etc., etc., <then close with triple end quotes>

CURVE_GL="0;80 5;29 9;17 21;8 33;5 100;0"""

will add a curve that puts out 80% of the defined channel at the white end, drops dramatically  as the gray inks come in, then tapers off to "0" at the black end.  (I use this curve to add Glop heavily in the highlights then taper off to no glop at the black end.)  A curve of: "0;100 100;100""" would add full channel output from white to black.

2) the second method is to go into PS and define an ACV grayscale curve, then drag and drop that curve's location on your computer after the equal sign.

CURVE_GL=/Users/RPB/Desktop/1800-ACVs/GLOP2.acv

Above defines the curve as the ACV file named GLOP2 that resides in a folder named 1800-ACVs that is on my desktop.

You can create the ACV file by going to PS>File>New (here you must make sure that the color mode is Grayscale, nothing else matters except the bit mode you want the curve to be in)>OK>Layer>New Adjustment Layer>Curves>OK (here you want to be in Pigment/ink % mode, make sure Channel indicates Gray)  Now define your curve and then Save Preset.  You must now define the location to save the ACV file with its given name.  You can then define that path after the = sign in the Curve_GL= line or with Finder and QTR you can drag and drop the path after the = sign.

Now process the text file as you would normally to create the curve.

There is one more caveat when using GLOP.  QTR will not print any channel onto an image that measures 255 (pure white) as QTR normally leaves pure (255) white as Paper White.  Here you must add a Levels Layer that converts white 255 to white 254 in your image before printing.

To your image add an Adjustment Layer by going to Layers>New Adjustment Layer>Levels>OK (Here change the 255 output to 254) >OK.  You will, of course, need to add this layer to every image you want to print with this curve.

Since you are printing out of QTR with multiple curves I would add the full amount of Glop you want to each curve then let QTR assign percentages in the Curve Mixing.

The above is an amalgam of information coming from Paul Roark's website for some Curve definition info and the necessity to change the 255 output to 254 and from articles on Ron Reeder's website as they relate to dragging and dropping path's to define Curve's with ACV files.

Good luck!