Spot color 1

[emkemner]

Is there a way to place a spot color in a grey scale image without changing the image mode from grey scale?

 

[Dweezel]

I wouldn't have thought so.
What is it you are trying to do with the image?

 

[Matzki]

If your image is greyscale, you must make it Multichannel to add spot color. This should not effect your levels of grey.

 

[emkemner]

I'm Creating a magazine ad for the trader magazine in grey scale with cyan spot color background. The photos i use in the ad are cmyk and i use them in large for large format 4color ads as well and didnt want to have to change each individual photo to grey scale. i have over 40,000 photos as it is and having to make coppies of them in grey scale just for the small ads would just cuase more confusion and give me more files to loose. So i was trying to create the ad in quark express and export it as a pdf with no background then convert it to grey scale in photo shop, then put in a cyan background. however when i change it from cmyk to grey scale then back to cmyk it doesnt print good becuase the grey scale images are made up of cmyk colors. so i need to keep them grey scale while putting in a cyan background. other wise im just going to have to convert all the photos to grey scale and have yet another 40,000+ images on my server. Wich is what im trying top avoid.

 

[Dweezel]

This might be of some use to you. I haven't read it in detail, but there's lots of stuff in this post about spot colours in grayscale images:

http://www.istockphoto.com/posts.php?threadid=3787&page=1

 

[blueark]

You are changing them from cmyk to greyscale and back to cmyk so you can add the cyan, is that correct? I'm not sure you're going about this correctly, but you could try doing this:

1: Convert to greyscale;
2: Select All, then go to Edit > Cut;
3: Convert to cmyk;
4: Open the "Channels" palette and select the black channel;
5: Paste;
6: Select the cyan channel and do whatever you need to do with it;

Now you have the greyscale image in the black channel, and provided you don't add anything to the magenta and yellow channels, you should be ok. In an ideal world, you should be able to just use Multichannel mode instead, but unfortunately many printers still have trouble with it.

If this gets the results you need, read the FAQs about setting up an action to do it automatically. If you've a lot of images, you'll only need to do it for the first one, and Photoshop will take care of the rest using File > Automate > Batch...

 

[emkemner]

Thanks Blueark I didnt even think of using channels, looks good now ill see if it comes back good.