Expert: Glen Demers - 9/29/2010

Question
QUESTION: Hello Sir,
     I am working with Adobe Photoshop CS4.I have tile design with me.I want to separate the colors,which are specified along with the design,from the design. Just CMYK or RGB color separation does not work for tile's printing. So need to separate color to the specific ones given.

     I have tried spot color separation using color range for color separation but when it comes to the variation and shading of different colors in a single design,it is not accurate what I get from simple spot color separation. Can you suggest me some method of separating all the tones and shades of a single color from the given tiles design?

ANSWER: Hello Hiral,

In Photoshop  you can add spot channels to a CMYK, RGB or Lab image or you can use multichannel mode for screen printing of colors that are not the standard four color process (CMYK). You can convert an existing image to multichannel mode and change the CMYK channels to different spot colors. Converting an RGB or Lab image will convert to CMY then change to multichannel. Files with spot colors need to be saved as DCS 2 .eps files.

Working with spot colors can be tricky because you can't use layers. If you add type to a spot channel it will be a type mask - make sure the type color is 100% black to be 100% spot color when rendered.

Using the magic wand or other selection tool to select the color of the design you want, go to "New Spot Channel" in the channel palette. Click on the color swatch and change color picker to custom to specify a spot color. Solidity will only affect the opacity of how the color is displayed. Spot channels are individual grayscale channels and can be edited using any of the tools.

You can change a channel's color by double clicking on the thumbnail in the channel palette and changing it using the same dialog box as when you create a new spot color. If you already have a design in Photoshop the easiest method may be to convert to CMYK multichannel and then adjust the channels to match the colors needed.

Hope this helps,
Glen Demers
Adobe Certified Expert, Photoshop 7
Prepress Technician, Best Printing Online
www.bestprintingonline.com

For more Photoshop tips please visit our help pages here: http://www.bestprintingonline.com/photoshop.htm


---------- FOLLOW-UP ----------

QUESTION: Hello Sir,

      The method you suggested was already tried by me. I have got enough command over the same. But it is bit time consuming as I am doing it professionally and at the same time,it is not accurate.

      As I came to know that every professional in this field uses color range to separate colors than going for CMYK separation and then customizing it to given colors,I want to switch to that method. So can you help me to have proper separation using color range only?

Answer
Hello Hiral,

To make separations from selections using color range, open a new document and make it the same exact size as your original. Change the mode to multichannel and rename the channels to the colors you wish.

In the original select the color using color range and click okay. Drag the selection over to your new document holding down the shift key. Once the selection is in the new document select the channel you wish it to be in the channel palette. Go to Edit>Fill... and in the dialog box for Contents Use: select Black from the pop up menu.

Repeat for your other colors. Holding down the shift key while you drag the selection over to the new document makes sure everything is registered.

Hope this helps,
Glen Demers
Adobe Certified Expert, Photoshop 7
Prepress Technician, Best Printing Online
www.bestprintingonline.com

For more Photoshop tips please visit our help pages here: http://www.bestprintingonline.com/photoshop.htm