QTR-Quadtone RIP

Apologies, I am resending this to the group to fix a few typos/mistakes in my original note that could affect people's diagnosis:



I'm trying Roy's new StepWedge tool and running into obstacles. I am a newbie at curves and and would be very appreciative if someone could look at what I'm doing and offer any advice.

The setup: Snow Leopard Mac, Photoshop CS4. I don't have access to a densitometer or spectrophotometer. The printer is an Epson 7000 with K6 inks. Printer works fine. (Good nozzle checks etc.)

QTR's stock K6 curves for the 7000 get me close, but with one major problem: They're not giving a smooth transition through the midtones. Instead, the midtones stay too dark, then fall off sharply around 30%-40%. 

When I try to modify the QTR profile following the instructions with the StepWedge tool, do I get a smoother transition, but overall a MUCH, MUCH DARKER result. 

I've tried the StepWedge tool several times. Here's the basic approach. Can you spot my mistake(s)?:

(1) I do a nozzle check on the printer to confirm all is well.
(2) Open the the "Step-21-gray.tif" in CS4. 
(3) Since CS4 on the Mac won't let you print with "no color management," I assign the tif a profile. I've tried several profiles, including "QTR-Gray Lab."
(4) Print the tif on Epson Enhanced Matte, using the standard QTR profile for EAM paper for the 7000. (Printer settings: 1400, unidirectional.)
(5) Using a Canon Lide 200 flatbed scanner, I scan the printout of the tif alongside a standard Kodak Q13 grayscale card. (The Q13 is new.)
(6) Open the resulting side-by-side scan in CS4, and run the StepWedge tool per instructions.
(7) Drop the resulting text file on to the "QTR-Linearize-Data" script, which produces a new text file containing lots of data that I don't understand, as well as a "linearize" line that looks roughly like this:

LINEARIZE="94.92 90.66 87.27 84.02 80.6 76.01 68.1 61.28 56.8 53.91 50.88 46.88 43.74 41.07 38.64 35.45 30.91 26.4 22.96 19.94 18.47"

(8) In my QTR folder, I create a new profile by making a copy of QTR's standard EAM profile for the 7000.
(9) I open that copy, replace the "LINEARIZE" line in it with my newly created "LINEARIZE" line, and then save and close my new profile.
(10) Then, I run the QTR 7000 install script. (This makes my newly created profile show up properly in my printer-dialogue box).

Lastly, I make a test print with my newly created profile and the test print is very, very dark.

Whew. That was a lot of words. Does any of that make sense? Do you see any obvious problems in my process?

Many thanks to all for any advice. I feel like I'm very close with this printer....

All the best,
JP




--- In QuadtoneRIP@yahoogroups.com, "jespes" <jesse@...> wrote:
>
> I'm trying Roy's new StepWedge tool and running into obstacles. I am a newbie at curves and and would be very appreciative if someone could look at what I'm doing and offer any advice.
> 
> The setup: Snow Leopard Mac, Photoshop CS4. I don't have access to a densitometer or spectrophotometer. The printer is an Epson 7000 with K6 inks. Printer works fine. (Good nozzle checks etc.)
> 
> QTR's stock K7 curves for the 7000 get me close, but with one major problem: They're not giving a smooth transition through the midtones. Instead, the midtones stay too dark, then fall off sharply around 30%-40%. 
> 
> When I try to modify the QTR profile following the instructions with the StepWedge tool, do I get a smoother transition, but overall a MUCH, MUCH DARKER result. 
> 
> I've tried the StepWedge tool several times. Here's the basic approach. Can you spot my mistake(s)?:
> 
> (1) I do a nozzle check on the printer to confirm all is well.
> (2) Open the the "Step-21-gray.tif" in CS4. 
> (3) Since CS4 on the Mac won't let you print with "no color management," I assign the tif a profile. I've tried several profiles, including "QTR-Gray Lab."
> (4) Print the tif on Epson Enhanced Matte, using the standard QTR profile for EAM paper for the 7000. (Printer settings: 1400, unidirectional.)
> (5) Using a Canon Lide 2000 flatbed scanner, I scan the printout of the tif alongside a standard Kodak Q13 grayscale card. (The Q13 is new.)
> (6) Open the resulting side-by-side scan in CS4, and run the StepWedge tool per instructions.
> (7) Drop the resulting text file on to the "QTR-Linearize-Data" script, which produces a new text file containing lots of data that I don't understand, as well as a "linearize" line that looks roughly like this:
> 
> 
> LINEARIZE="94.92 90.66 87.27 84.02 80.6 76.01 68.1 61.28 56.8 53.91 50.88 46.88 43.74 41.07 38.64 35.45 30.91 26.4 22.96 19.94 18.47"
> 
> 
> (8) In my QTR folder, I create a new profile by making a copy of QTR's standard EAM profile for the 7000.
> (9) I open that copy, replace the "LINEARIZE" line in it with my newly created "LINEARIZE" line, and then save and close my new profile.
> (10) Then, I run the QTR 7000 install script. (This makes my newly created profile show up properly in my printer-dialogue box).
> 
> Lastly, I make a test print with my newly created profile and the test print is very, very dark.
> 
> Whew. That was a lot of words. Does any of that make sense? Do you see any obvious problems in my process?
> 
> 
> Many thanks to all for any advice. I feel like I'm very close with this printer....
> 
> All the best,
> JP
>