spot colour - transparent background

[jackitin63]

What am I missing? I need to convert a cmyk halftone image into a single spot colour with a transparent background to be used in Illustrator. I've tried several things which either bring the image in transparent - but doesn't bring in the spot colour .... or obviously i can bring it in as a tiff or eps, and it brings in the spot colour but it's not transparent!

I've been trying to resolve it for hours! Can I truly be this dim??? Any help would be greatly appreciated!

 

[MarcusStringer]

You could always colour the transparent image in Illustrator

Marcus

http://www.midlandtypesetters.com.au

 

[Foamcow]

Unless a file created in photoshop has an Alpha Channel Mask or a Clipping Path Mask then it will have a background.

Foamcow Heavy Industries - Web design and ranting
Toccoa Games - Day of Defeat gaming community
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"I'm making time

 

[jackitin63]

Sorry, I should have re-read my post. What I should have typed was ... I've tried several things which either bring the image in with a transparent background - but doesn't bring in the spot colour .... or obviously i can bring it in as a tiff or eps, and it brings in the spot colour but the background is not transparent. If i bring it into illustrator as a greyscale or cmyk .eps the "line" and "fill" aren't options.
The original jpeg that i'm trying to turn into a single spot colour is an image of a plasma screen if that helps?
Thanks

 

[blueark]

Before you bring the grayscale image into Illustrator, draw a shape, such as a rectangle, the same spot color you're trying to achieve. Place the grayscale image on top of that, and resize the rectangle to fit the image. Select both the image and the colored shape and open the transparency palette (Window > Transparent). In its fly out menu, choose "Make Opacity Mask". That should give you what you need.

 

[jackitin63]

Thanks for that blueark. I tried the "make opacity mask" (i didn't even know it was there!) and thought i was onto a winner, but (sorry) i didn't mention this but it's a litho print job so if i go to output the spot colour film it shows my image as a continuous flat screen, ie it's printing the shape of the image but not the image itself. Looks perfect on screen tho.

I am obviously still missing something simple cos people must have to output spot colour images with a transparent background over another spot colour all the time.

Anyway, all is not lost, at least i learned something new! Any more ideas?

 

[Foamcow]

If it's going over another spot colour then just make the background the same as the background spot colour.

No need for a transparent background at all.

I am having trouble understanding quite what you are doing though. Perhpas if you said what it is you want to achieve rather than specify a method that you think will do it?

Foamcow Heavy Industries - Web design and ranting
Toccoa Games - Day of Defeat gaming community
Target Marketing Communications - Advertising, Direct Marketing and Public Relations
"I'm making time

 

[jackitin63]

Thanks foam, point taken. I'll do my best. OK I'm producing a 2 col letterhead, 2 spot cols 032 red, 072 blue. Customer has done his own artwork in CorelDraw saved it as a PDF which i can open in illustrator. He doesnt want to pay 4 col process prices so we need to turn any images he has on it (TV screens n DVD boxes etc) into single col halftones of the 072 blue. And reproduce the artwork into a format which will colour separate to imagesetter.

The image of the TV screen sits halfway on a box of red and halfway on the white paper background, so if i leave the background as white, it knocks out the red box. I can bring the images in as greyscale (with no background) but then its gonna be a 3 col job (maybe thats the best idea and i'll foot the cost of the extra col myself haha!)

Thanks anyway foam, appreciate the reply

 

[MarcusStringer]

Do you own Pitstop?

http://www.enfocus.com

Marcus

http://www.midlandtypesetters.com.au

 

[blueark]

If you're stuck, you could always leave it as grayscale, and change everything in 072 to grayscale. That way it will separate out to two plates. Just tell the printer the black plate should be printed as 072. It makes no difference at that stage as long as they know...