Making Spot colors in Photoshop

[Phatgi]

I mainly work in Adobe Illustrator and vectorize most the stuff I work on, but I have a bunch of .jpeg files for the sponsors to go on the back of a tshirt. How can I pull all of these logos in to photoshop and make them 1 spot color to print the back film? I just haven't had the time to sit down and play with spot colors in Photoshop. All the logos are different colors also.

I apologize in advance but I just haven't done much in Photoshop for the screen print side of graphics. I do use photoshop to produce banners and vehicle wraps and other art, just stating this to let you know that I am not new to photoshop just inexperienced in doing spot colors.

[tpitman]

Since you say they'll all be one spot color, most people just open 'em in Photoshop and change the "mode" to grayscale if there are tints in the art, and output them as b/w halftones.

[sqslabs]

To add to the above post, once your file is in grayscale mode, you can easily adjust the black/white ratio by using the image-->adjustments-->curves option.  I'd recommend doing this to each logo individually as this would only work on all of them if they were all the same colors to begin with.  What you'll end up with is your darkest colors as black, and the lighter shades as greys which you could then convert to halftones. 

As an example, if you had a logo which was mostly red with some lighter tones in it and you just converted to grayscale, you'd end up with all grey tones, and a completely halftoned logo with no solid areas.  On the other hand, if you adjusted the curves on the dark end of the spectrum a bit, the red color would be solid black and the other tones would be halftones of that.

If you are looking to just use the predominant color in the logos and white out the rest, use the "Select Color Range" option on the original logo (in color), select the color you want and use the slider to adjust the selection.  Once the selection is made, create a new layer and fill the selection with black (edit-->fill). This layer will now contain a black and white version of the image.

I use these as well as a few other techniques, depending on the logos and the desired result.  If you'd like to post one of the logos and give an idea of what you'd like it to look like, I could probably be a bit more specific.

edit: fixed photoshop menu discrepancy

[Sbrem]

Also, if you have a color image, before you go to grayscale, you can also adjust how each color will change to gray by using Image-Adjustments-Black and White. In there, you can choose, say yellow, and adjust it's slider so it will come out darker or lighter in the grayscale image, the same is true with greens, blues, reds etc. So, you can adjust how each color will change before you actually go to Grayscale. There are lots of ways to adjust images, each with their own strengths and weaknesses. As you get to know them it will get easier to deal with all the crap images we all receive regularly...

Steve

[3Deep]

Steve, I need to sit down with you and take an Illy course, I've learned a lot just by reading your post (shortcuts and hiding goodies I didn't know about)

D

[kirkage]

I like taking the gray scale images in photoshop and converting to bitmap. Then I place those bitmap files into illustrator and color them with a spot color or anything you want.

[Sbrem]

Steve, I need to sit down with you and take an Illy course, I've learned a lot just by reading your post (shortcuts and hiding goodies I didn't know about)

D

Yo Darryl, that's a Photoshop thing above, but I always place them in Illy before printing. And as Kirkage added, after you go to grayscale, you change to bitmap, use the halftone function so it's saved with your favorite line count and angle and shape, then place it in Illy and make it any color you want. But the "Black and White" function under Image/Adjustments was a real eye opener, check out some youtube vids, you'll see right away how handy it can be before actually  converting to grayscale...

steve

Steve