How to Sep a mix of spot colors and gradients in Photoshop?
How can I separate this with Photoshop? (PS 7 if it matters.)
I know this would be simple for someone with more Photoshop experience.
I now can do true spot seps, and CMYK, thanks to this forum! I can use the "stroke" command for traps, and print halftones using Ghostscript and GSView, and make dense positives. Yip Yip Yahoo. That puts me at almost beginner level.
I hate to come to the well yet again for something this simple, but Photoshop mixes with my past vector experience like oil and water. I AM gaining, however.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
The pdf is in CMYK, no spots, you should be able to drop it into Illustrator and do a quick sep to the Postscript Driver there. Then print from Ghostview.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
Quote:
Originally Posted by PositiveDave
The pdf is in CMYK, no spots, you should be able to drop it into Illustrator and do a quick sep to the Postscript Driver there. Then print from Ghostview.
Well, the file I opened was in RGB mode. Did the one I attached open in CMYK for you?
Regardless, I wanted to sep this in Photoshop, because that's what I am focusing on just now. I'm even worse at Illy.
I worked with Signlab for 15 years and Photoshop is a whole new world. It's like the folks at Adobe have cloaked the simplest of processes with obscure terminology. ie: Stroke? Why not outline! (OK. Perhaps that is raster-speak.)
This file can be separated with Photoshop easily, no?
Re: How to Sep a mix of spot colors and gradients in Photoshop?
If I'm following what you are wanting correctly, this is the way I just did it.
- Duplicate your layer
- Turn off a layer
- Select layer that is on
- Select all the yellow with the magic wand tool (be sure to get all the yellow, I deselected the Continuous button in the magic wand tool options)
- Delete the yellow (this is now your purple layer)
- Deselect
- Hold down Command button while clicking the purple layer icon. (command button is on a mac, not sure about PC) This should select the purple (and white) remaining.
- Turn on the other layer and select it
- Hit delete (this is now your yellow layer)
Now the colors are separated, but still in RGB/CMYK... don't matter in this case. An easy solution to this is to do the following...
- Convert the file to grayscale (DO NOT MERGE LAYERS)
- Select the purple layer
- Bring up curves (image - adjust - curves or cmd M).
- Change the input until the blackest gray becomes 100%. The Info pallet will allow you to see what the percentage of the black is. In the file I am using, I had to shift the input to 80 (b/c the purple converted to an 80% value of gray when converted to grayscale) If you are worried about the gradient shifting, you can add anchor points (click on the curve) that will stop the adjustments from effecting the entire image. For example you could effect the 75% to 100% but not too much below 75% by adding anchor points from 75% and below. This isn't an exact science (in my opinion). Play around with it and you'll begin to figure it out. I didn't see too much of a shift on the gradient, but you should be the judge of that.
- Repeat the same process on the yellow. I had to adjust the Input on the curves to 7! Once yellow was converted to grayscale the yellow has very little value.
Now you will have to account for a trap, registration marks, RIPing, blah blah. But, I'll leave that all to you.
I hope I helped. I can be more confusing then helpful sometimes.
FYI, I saved the file, if you want it, let me know.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
RGB then, it wants to separate to CMYK.
Did you make it with spot colours?
If you want outlines, get Corel.
If you want to separate to spot colours in PS, then you need to create a new spot colour channel and work in CMYK.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
[quote=PositiveDave;491646]
If you want outlines, get Corel.
quote]
Ha! I'll just pretend my strokes are outlines! Actually, I think my problem lends validity to the old saying, "You can't teach an old dog new tricks." Which is not entirely true, but I am certainly not learning this at the speed in which a 12 year old would.
And this art came from the customer. I didn't draw it myself.
And thanks again Dave, I will try it in CMYK mode.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
Quote:
Originally Posted by typo_joe;
FYI, I saved the file, if you want it, let me know.
Yes, please. If I fail or succeed on my own, in any case I can use yours for comparison.
I wasn't feeling well this afternoon and decided to lie down for a while. I will try your instructions now, and post back.
I am PC based, so I may have to do some more head scratching to interpolate.
And yes, I have opened the pdf in my even more dinosaur Illustrator 10, which I have had lying around, unused, for several computer millenia. The files actually came to me in ai format too, but I am puzzled by your proclamation that they were sourced from CS3. Is there some embedded code that tipped you off? I have no idea.
Quote:
Originally Posted by typo_joe;
Even if you don't know Illustrator well, converting CMYK/RGB colors to spots is a lot easier in Illustrator than Photoshop. (IMO)
So, maybe I'm thinking wrong. The gradient in the file I sent you--I wouldn't call that a true spot color for the purpose of accurate definition. I thought a gradient was a different animal. I know they gradients are represented as halftones in screenprinting, instead of continuous tones.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
Quote:
Originally Posted by Stan Hoover
Yes, please. If I fail or succeed on my own, in any case I can use yours for comparison.
I tried, but it the attachment fails. I think the file size is too large because of the layers. If you want to PM me your email address, I'll try to email it to you later.
Quote:
Originally Posted by Stan Hoover
The files actually came to me in ai format too, but I am puzzled by your proclamation that they were sourced from CS3. Is there some embedded code that tipped you off? I have no idea.
I know this because when I "get info" on the file (get info is like properties on the PC) it says Content Creator: Adobe Illustrator CS3. Plus when I open it in my Illustrator it says that it has been created by a newer version of Illustrator. However, it doesn't say which version.
Quote:
Originally Posted by Stan Hoover
So, maybe I'm thinking wrong. The gradient in the file I sent you--I wouldn't call that a true spot color for the purpose of accurate definition. I thought a gradient was a different animal. I know they gradients are represented as halftones in screenprinting, instead of continuous tones.
No, I wouldn't call the gradient a spot color. In the file you gave, it is a gradient of process colors (or RGB). Gradients can be either. It just depends on how it was created.
You are correct about gradients. They do need to be converted to halftones (via RIP software) in order to have them reproduce correctly when being burnt onto your screen. With a contone (shorter term for continuous tone) gradient, you will have very poor results after exposing. Search the forums, I believe there is an explanation of what happens when you burn a gradient before converting to halftones.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
Hey typo_joe, I sent you a PM with some emails that oughta work. I don't know whats up with yahoomail and sbcglobal.net but for several days, email is hit or miss, with no real explaination. Prolly spam related, truth be known.
Re: How to Sep a mix of spot colors and gradients in Photoshop?
in photoshop select image-mode-grayscale and then image-mode-bitmap set the output 600 or its up to you then select halftone screen click ok then set the frequency 30 and angle 45 shape round ok your done
How to Sep a mix of spot colors and gradients in Photoshop? 
