How to adjust pictures in duotone mode?

[emil_ems5]

<p>I am working on a photo book with b/w prints that I would like to print in tritone mode.<br>

My method of working is as follows:</p>

<p>1 I make an original print in the book size, using my Epson 3880 in ABW mode.<br>

2 Starting with that file (optimized and sharpened for offset print), I convert it to greyscale. Thereafter I use duotone mode and choose the Adobe standard form [black; Pantone Cool Gray 9CVC; and Pantone Cool Gray 2 CVC).<br>

3 I do not adjust the curves for the three colors. Instead i use an ordinary curve adjustment layer to bring lightness values as close as possible to those in the file for print (1) above. <br>

4 To "proof-print" that version, I convert back to mode RGB and print the file again in Epson 3880 in ABW mode. if print (4) equals print (1) I assume that I have a file optimized for offset printing. </p>

<p>Since I never have done such separations for offset printing before, I would like some advice from the Community, before communicating with the printer so as to ensure that I get a result in the book as close as possible to my print.</p>

<p>Question 1: In Adobe's Duotone Dialogue there is a box called "Overprint colors". Since I chose one of Adobe's standard forms, this dialogue is already filled in. But what is the meaning of this Dialogue? Should settings be adjusted after talking to the printer?</p>

<p>Question 2: The black color in Adobe's standard form is just ordinary "Black". Is this OK in a book, where ordinary black is also used for text? Or should I replace it with a Pantone Color?</p>

<p>Question 3: The Duotone file can be saved as a PSD file in Photoshop. Is it OK to place this file in the Indesign file for the book? Or should another saving format be chosen? Or should I ask the printer for the right format?</p>

<p>Question 4: How to ensure that the maximum ink-limit for the offset printer is not surpassed, given the maximum value obtained from the printer. Is there a fool-proof warning to be found in Photoshop (the warning in InDesign is not reliable)?</p>

<p>Any additional advice on how to communicate with the printer would of course be extremely valuable and welcome!</p>

[mendel_leisk]

<p><br />Can't really address your questions, but this might be worth a read, regarding dual tone:</p>

<p>http://www.computer-darkroom.com/tutorials/tutorial_2_1.htm</p>

[howard_owen]

<p>Here's a little info from Adobe <a href="http://helpx.adobe.com/en/photoshop/using/duotones.html">http://helpx.adobe.com/en/photoshop/using/duotones.html</a></p>

<p>Another source: <a href="http://www.tipsquirrel.com/creating-a-duotone-image-in-photoshop/">http://www.tipsquirrel.com/creating-a-duotone-image-in-photoshop/</a></p>

[emil_ems5]

<p>Thank you kindly, Mendel and Howard, for your links, which are useful. However, they do not seem to answer all my questions, which stem from trying to prepare myself optimally before contacting any printer. In particular, Qu 2 and 4 are not really answered in the publications in question. </p>

<p>I had hoped to get some response from a fellow photographer who has been through the practical aspects of preparing photos for tritone printing himself. But maybe this is an art that is not practiced anymore? If there would still be some practicing expert out there somewhere, I would highly appreciate some help!</p>

[digitaldog]

<blockquote>

<p>4 To "proof-print" that version, I convert back to mode RGB and print the file again in Epson 3880 in ABW mode. if print (4) equals print (1) I assume that I have a file optimized for offset printing.</p>

</blockquote>

<p>That may be part of your problem. ABW is a 'black box' in terms of converting data to print B&W and I suspect the duotone isn't supported (that appearance is converted when printed). <br>

Next, what does the actual printer need? RGB, an actual Duotone? You may indeed need to create a true duotone, then convert back to RGB as you did for the Epson (color should remain the same), then send that RGB data to the printer to convert to CMYK. You need to ask them what color model and file type they actually need. </p>