开云体育

开云体育

开云体育

I use QTR on a PC with a P800 printer, which replaced the 3880 and 3800. I use the front feed to avoid “pizza wheel marks” and print my digital negatives on Fixxons for classic cyanotype process.

I make my own curves with the Tools>Curves Creation. Each ink has a drop down choice of: Not Used, Gray Ink, Toner, Toner2, Copy curve from and Load Curve. Click on Load Curve and Curve and a Window or Panel opens with a Tab “Point List” then enter these value for a reverse “S” curve.

0;0 3;19 5;21.5 10;24 15;26 20;28 25;30 30;32 35;3440;36.5 45;39 50;41 55;44 60;46 65;48.5 70;50.575;53 80;56.2 85;59 90;63 95;71 97;81 100;100

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Now when you put a Density Limit in for an Ink and choose Load Curve and put these values in Curve the reverse “S” curve will reduce to the Density Value, say 60 for screen shot example.

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So I use Yellow Ink for my main UV blocker ( actually a UV filter, as the MK or PK inks block UV light) and a little LK ink.

See Attachments:

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How to Linearize: Measure a 21 Step Wedge with a Datacolor Spyder or other device to measure Lab values (maybe Density values work too) and use the QTR linearize feature or the Spyder software has a QTR linearize feature. BWmastery’s Richard Boutwell’s website had and excellent Excellent spreadsheet to Linearize but I don’t see it today.

All 3 of which I have not used since I purchased in 2017 an early version of QCDN for the PC.

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The Yellow ink in the 3880 and 3800 may be a better “blocker/filter” so you may reduce to a 50 density or lower depending on tests.

Hello Williamskg

Unfortunately, both of the easier methods of creation of the QIDF are only automated in software on the MAC, which is why people keep telling everyone "Just buy a MAC"? (Boutwell and Mark Nelson's PDN methods are two that work well but only on a MAC).

That being said, the PC method in the book works well and is what Sandy King teaches.?

However, there is a very easy method developed by Ike Eisenlord that is described in the book on pages 52-53 that may get you going easier that the more complex method that is currently causing some frustration. (see pages 52-53 for this method. It avoids QuadToneRip entirely but instead just applies a curve as an ACV in Photoshop.? Since it prints with all inks at once, there are two downsides -- one is that it wastes inks by using ink channels that do not block UV, and so much ink may be applied to an OHP that it runs before drying.

You will find QuadToneRip to be superior? so let's move forward:

A couple of questions before we proceed - you did not mention whether you had these
A) Do you have a reflection densitometer? Or alternatively a scanner? You will need one to read the values starting with your results from the ink calibration negative.? You mention a Spyderprint so I presume you can get reflective values from that
B) Stouffer step tablet. You cannot use the Epson to substitute, but you could do an alternative test using the OHP and a series of timed steps.?

You are going to do the following to create a 1-part QIDF for your process
0) using the Stouffer step tablet, print in your process and find the Dmax value for the time of exposure.. see page 39
1) Print the ink calibration negative on your printer(3800)? see page 40
2) Process the resulting image in your process (Cyanotype)? see page 40
3) Read the results using a reflection densitometer (alternative, use a scanner). Select some values for the LIMITS for each selected ink (as described in the book) on page 40
4) Make a series of prints of the 21 steps so steps 0-5 and 95-100 are the appropriate values? see page 41
? ? ?(See Figure 4.14 in the book.? Select the QIDF that produces the following result:? (its the top one, shown as #1?
? ? ? ? ? ? step tablet box 0 is paper white
? ? ? ? ? ? step tablet box 5 has a tone
? ? ? ? ? ? step tablet box 100 is your Dmax? value from 0 above
? ? ? ? ? ? step tablet box 95 is less black than step 100
5)? Using the QIDF selected in 4 above, read each of the values from step tablet box 0,5,10.....90,95,100? see page 42-43
? ? ? enter those values on the linearized line
6)? you can use this QIDF for your negatives.

To answer your specific questions:

Q: What I don't know is, where do I enter them?? Are they the Density or the limit values?? If they're Density, how do I determine the limit values?? If they're Limit values, how do I determine the Density values?

A:? As shown in examples, pages 44-46, the values read by the reflection densitometer are on the LIMIT lines for the selected inks.? The default Density for all inks is 100.? So in the Curve Creator tool, set Density to 100 for all inks, and paste the values read into the LIMIT box. If editing a QIDF text file, follow the example on page 44.

Q: I've included a poor quality cell phone picture of the print made from the Calibration Mode transparency I printed (my flatbed scanner is not working well).? It looks like I should be using Black (PK in my case), Yellow, Light Black (LK), and then Probably Light Light Black (LLK) and maybe Cyan inks, omitting the light cyan, light magenta, and magenta inks.?

A: you are correct - the K, Y, and LK are the ones to use for the simple 1-part QIDF.? You won't need the others unless you are building a 2-part or 3-part curve.
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Q: Am I on the right track?? If you are willing to provide advice, correction, or further guidance I'd be very grateful.

A: you have a good start. Message me directly in email ( hit Reply to sender) and I will be happy to work you through the process.
Welcome to QuadToneRip the hard way (PC !)
Don

1. Create a .qidf ink definition file for my printer and then
2. Linearize the curve(s) so that when I print negative files, they are printed as usable negatives

• I have installed QuadTone RIP
• I have selected my printer (Epson 3800)
• I printed the Calibration Mode image on Pictorico TPS100
• I made a cyanotype (my preferred process) of the Calibration Mode transparency to identify what inks block UV best.

1. For each ink I wish to use, find the percentage square that is my DMax - the darkest patch for each ink
2. For each ink I wish to use, halve the percent under the patch that is DMax for that ink
3. Put the values somewhere