New to 4 Color Separations in Photoshop

[compartista]

Do you have to have a transparent background to make color separations? 

I am color separating my artwork in photoshop, on the channels layer, making alpha channels, and inverting the color, changing alpha channels to pms color, then saving as a DCS2 file, and exporting, when I bring it into Illustrator, I can see the background as white? Is this right or what am I doing wrong? 

When I hit print to pdf, it shows the whie background? Don't laugh I'm new, but I'm going to get this, I have to it's my job now, and I 've been fired from too many, because there is no one there to teach how to do it right. I'm sure you can all relate. Thanks! I have other questions as well.

Do you have to be in CMYK mode to make the best print in photoshop, I see people doing RGB, I was always taught that's a no-no. 

[D Fosse]

Start by describing exactly what the goal is here. Normally "4 color separation" just means CMYK.

But CMYK isn't just CMYK. You need to know which CMYK profile to use. For that you have to talk to the printer.

[Derek Cross]

Are you ultimately going to have your work printed as CMYK by a commercial litho printer or on your own desktop inkjet printer, or do you want to have it printed in say four spot colours say screen printed ?

Never produce a PDF by printing - use Save As and select the version your printer advises, usually PDF/X-4.

[compartista]

Thank you for your response. Ultimately it is an image that is going to be printed on a tshirt, so it will be printed on films, for screen printing yes. 

[compartista]

Thank you D_Fosse, we are the printer shop. I watched you tube videos that said the best way to color separate the artwork is CMYK for screen printing. I understand the color profiles you’re talking about, I use color books/Pantone’s/uncoated.  Which several people have recommended on YouTube. I appreciate your response. I hope I’m explaining myself correctly. This is a learning curve for me. Once I’ve separated the colors, I print the films and they get turned into a screen. I just figured out how to line up the registration marks, 😂 it’s a process, but it’s starting to make sense. 

[NB, colourmanagement net]

What do you mean by "4 color separations" Compartista?

4 color separation is a term we usually use to refer to the process of converting an RGB file into (normally print ready) "CMYK"

IF you are making CMYK then be very careful, as D Fosse mentioned you need to be provided with good information (by the printer) about what CMYK profile to use in Photoshop.

Hres a bit of background reading about ICC profiles:

https://www.colourmanagement.net/advice/about-icc-colour-profiles/

and about printing press colourmanagement

https://www.colourmanagement.net/advice/prepress/

I hope this helps

neil barstow, colourmanagement.net :: adobe forum volunteer

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[compartista]

Thank you NB for the information. 

I will read this and hopefully it will clarify about color management. 

[Derek Cross]

As I understand it, it's not a CMYK workflow but four Pantone (spot colors) printed via screen printing.

[compartista]

Yes Pantone colors, but I’m wondering from what I know Pantone colors are expensive, but that’s if you’re working for printed material. As far as I know my shop doesn’t charge for Pantone colors, I don’t handle the invoices, I just print films. So I pick Pantone colors because they are available in the color books. Should I be using these colors, or should I be using process colors? I know it depends on if it’s a company logo and they do specify the exact color, but most of the time, the t-shirts we print are not related to any organization, their just random designs with many colors. If you can imagine, and I know you can 😂, those extreme looking T-shirt graphics with about 6 different colors. It’s crazy. But I love it. I also printed some vinyl banners today from Illustrator and that was fun, but a lot of steps to get that printed on a nice big Roland.