Doing duotones

[marlene]

I've been working on a publication that includes about two dozen duotones, so I have been reading up on the topic.

Real World Photoshop (5) talks about screen angles, but I'm unclear as to whether that's something I'm supposed to somehow set up in the duotones, or something I talk to the printer about.

And what does the "image interpolation" option (in the save dialog) mean? I can't find that in the book or in the Photoshop help file. It might have nothing to do with duotones, but I'm curious.

Last, when I print out color seps on my LaserJet, I notice that both color seps for the duotones appear to print out identically. Is that supposed to happen? I had expected one sep to look different from the other.

mxh

[ktinkel]

… when I print out color seps on my LaserJet, I notice that both color seps for the duotones appear to print out identically. Is that supposed to happen? I had expected one sep to look different from the other.
I have never made my own duotones on the computer, but often spec’d them in the good old days.

Normally, the second color would be ghosted — its solids held to 60%, say. So although its neg would contain the entire image, it would be less dense. Depending on the two colors being used, the black might also be suppressed slightly.

You control the angles to avoid moirés, but I always left that up to the printer. Of course, that was in the good old days when the printer actually performed a lot of the production work.

Now what this has to do with Photoshop and duotones is way beyond me.

[Norman Hathaway]

No need to set your own angles.
Normally the tw oplates wouldn't look identical.
It's up to yo uto decide whether you want 'equal density' duotones- or if one color is stronger than the other.
One thing to keep in mind is that you should ensure that the colors are stacked in the order you want them to print (black 1st, color 2nd etc.)

[marlene]

Now what this has to do with Photoshop and duotones is way beyond me.

It's way beyond me, too, but the job was two spot colors (Pantone 335 and 2685) and I didn't want all the mug shots to be either green or purple!

mxh

[marlene]

It's up to yo uto decide whether you want 'equal density' duotones- or if one color is stronger than the other.

I just sort of eyeballed the duotone settings in Photoshop, I'd say the density IS pretty much equal.


...ensure that the colors are stacked in the order you want them to print ...

Hmmm. How would I decide? The green (PMS 335) was on top, purple (2685) underneath.

It's moot now, though, since the files went to the printer late this afternoon.

It'll be interesting to see the results.

mxh

[Dave Saunders]

I've done a lot of duotones over the past few years almost exclusively with Black and Pantone 201. I started out with curves that were very similar, each lightening the midtones by about 20% and going to 90%.

But over time, I gradually slackened off the Pantone curve so that it lightened the midtones by about 30% and going up to 70%. The resulting printed images were much more pleasing. The more subtle use of the second color resulted in pictures that popped a whole lot better than they used to when there was just too much of that deep red/maroon.

Dave

[marlene]

...lightened the midtones by about 30% and going up to 70%

You mean on the curve, where it says "50" (which I'm guessing is the middle of the midtones) you'd enter 30%, and at "100" you'd enter 70%.

I really am foggy on how all this works. I think I need to re-read Real World Photoshop and pay more attention!

mxh

[Dave Saunders]

Kind of. Usually, I just grab the curve and drag it. But entering the numbers has the same effect.

Dave

[marlene]

I ran into a major snag that is apparently a Quark glitch. I'm using Quark 5 for Windows, and when I imported my duotones into my Quark file, I did NOT see any new colors showing up on my swatch palette, so I assumed I had remembered to name the Pantones correctly in Photoshop -- being consistent with the "CV" or whatever was after the Pantone number.

And I double-checked my Quark color separations list.

However, I found out that I had NOT been consistent with the color naming, and had to go back to rename one of the Pantones in all two dozen of my duotones. What a PITA!

Next time I will pay more attention.

It seems to me that when I used Quark 4, if I had a duotone with a color named slightly differently from the Quark palette, it would show up as a second color (e.g., I might have Pantone 2685 CV and Pantone 2685 CVC in the palette), which would flag the problem to my attention.

But I could be disremembering ...

mxh