Duotones

Can anyone steer me to a site for some education on duotones?. Specifically I want info on how to adjust curves so that solid areas in the grayscale image do not come out at 100 percent in the 2 spot color separations.

Thanks
Bob

Can anyone steer me to a site for some education on duotones?. Specifically I want info on how to adjust curves so that solid areas in the grayscale image do not come out at 100 percent in the 2 spot color separations.

Thanks
Bob

Hi Bwright -

Looking at the date stamp of your post, you may already have an answer to your question by now from elsewhere.
The quick answer to your question lies in the attached image in where and how you can find the curves dialog to adjust both the black and spot channels. Choose the ink you want to adjust, then click on the "curves" icon (left) next to the swatch. This will bring up the dialog. Next, you can either enter values in the parameter boxes (#'ed 0 to 100%) or, you can adjust the diagonal line interactively. It also helps to have a calibrated display or monitor so you can see your proposed changes as accurately as possible.

Hope this helps, good luck-

Wayne

Thanks for the reply, Wayne. I wasn't really asking for how to adjust curves, but rather what values to prevent the solid areas from coming out solid on both plates. Do I just reduce the max value to 85 or 90% to cure the problem? I am hoping to have a workable solution before paying for the film negatives to prove it out.

Bob

Bob,

"""Do I just reduce the max value to 85 or 90% to cure the problem?"""
I would assume that. Just adjust to "taste" and do it to both channels within this dialog. If you have a postscript driver or the like, proof both separations on your inkjet if you can.

Better still, talk to your printer/bureau, get their opinion on your concerns. If they want to charge you for a quick assesment or advice, go elsewhere and feel free to do so.

Wayne

Unfortunately I am the computer guy in the printshop and I have talked with a couple of service bureaus, a bit advanced for them, they say. So I am pretty much on my own for now.

So if anyone is curious, I reduced the curves for both colors, 0, 60% > 55%, 100% > 90%, set transfer function straight line 100% > 90%, 0 > 0.
Screens and Transfer set in Photoshop, Transfer to overide printer’s default functions checked. Saved as eps with Include Halftone Screen and Include Transfer Function checked. This should override the image setter settings, but as a precaution I also had the service bureau match my screen settings. Packaged in InDesign for output, thought I would go Adobe all the way this time.

Film looks good, we should print today. I hope I have taught myself something good with this. I had a problem proofing the high color areas on my laserjet 4 PS 600 dpi, I think this was a limitation on the printer, plugged solid in the 100% areas.

Thanks for the help, it boosted my confidence.

Bob

Glad to see that...

Yes, I thought you'd get mixed results from proofing on the laserjet. For what it's worth, and if the job is worth it too,.. I was going to suggest "colour keying" from test film (cheaper) first, before committing to plate. And hey, I'm no season "vet" either. I think I've done 2 duotone jobs in my life. The thing is, I sweet talked my way into the designers area and for better or worse,..watched the process from start to finish. I try to see as much of both ends as I can just short of asking for an entry level job! I suppose though, it's getting to that point.

Anyone gotta a second hand Mac? http://www.talkgraphics.com/images/smilies/wink.gif

W