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How do i make two color images for color separation 3

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yuendos

MIS
Nov 4, 2003
19
PH
Hi. I recently have to do a job wherein it requires that the image to be used has to be in two color cmyk so as to be ready for color seperation. my design if in four colors. how do i go about into changing it? i would like to you cyan and black for this certain image but if i turn of magenta and yellow the image is all screwed up. is there a way to use two colors but still have a presentable image?

thanks.
 
but if you give it to a printing press and they make color separations they will use cmyk, and duotone will still appear as a four color graphic. what i want to try to do is make a two color cmyk that will still look nice.
 
Duotone is a different color mode to cmyk. You can specify two process colors if you want, but your printer shouldn't convert it to cmyk to make separations.
 
If the printer is requesting a 2-color original, they will print it using 2 colors. They want a duotone. They would not waste time and run 2 extra passes when they #1 didn't have to, and #2 (since they asked for 2-color) are not equipped to. I cannot imagine any printer asking for only 2 colors but in CMYK... unless I am missing something in the translation here....



When in doubt, deny all terms and defnitions.
 
I see that it has been a few days since the last reply, but in case anyone else takes a look at this, maybe I can be of some help...

I'm in the prepress department at a print shop which runs almost entirely 2-color jobs. I think that maybe what the printer in this case was trying to ask was for yuendos to keep the image in CMYK mode, but delete all information in 2 of the 4 channels; so that when they printed separations, the only 2 channels used in the document would be the only 2 plates. I have occasionally asked customers to do this if I thought that trying to explain how to make 2 individual grayscale (or bitmap) tif files for each color plate would be too confusing. I have also had to do this for some customer files given to me once in a while. It's not a very pretty way to do things, but it works in a pinch.

As far as duotone is concerned, it's not the only (or best) option for 2-color printing. It really depends on the job because a duotone makes for very tight registration, which usually means higher price tag! So ask your printer before giving them a duotone file.
 
signal


Thanks for that explanation. Seems you can learn something new every day if you aren't careful!

When in doubt, deny all terms and defnitions.
 
yes signal49, thats what the service provider is trying to make me do. my problem is i dont know how to do it, turning off magenta and cyan colors. and if i turn it off is the quality of the graphic still presentable.
 
I'm glad I was able to help with the explanation :)

You can't just turn off the 2 channels, you have to actually go into each one, select the whole artboard and delete (to white). Then go into the 2 remaining channels and bring the levels up (darker) until it looks ok when you view them together. It IS going to look weird if it's a photograph because you'll only be looking at Yellow and Black - unless those are close to the colors you're going to be printing with. Don't delete the other two channels or you'll end up with a multichannel file (instead of CYMK) and you have to save as another file type which gets a little confusing, and some print shops won't accept it anyway. As far as it looking presentable, that all depends on your original resolution and what your final goal is, and to some extent what spot colors you're going to use.
 
how do you actually go into each channel to delete it? my image is already in cmyk mode. thanks again for the help.
 
when opened in photoshop look in the channel palette. there you will have 5 channels; cmyk (composite), cyan, magenta, yellow and black.

pick the magenta channel, CTRL+A (mark all), delete.

same goes for cyan channel.

best regards

Rotbol
 
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