[teezecrost]

Hey everyone. I know this has been discussed many times on here, but sometimes it pays to reword/re-explore things. I'll keep it concise:

When does everybody use CMYK over Simulated Process, and vice versa. The consensus seems to be that Discharge underbase makes life much easier when printing CMYK on dark fabric. True?

 

[Alan Buffington]

Here's my take.

CYMK - great for designs with lots of different colors, limited however to printing on white or onto a discharge print for black t's but this will shift colors due to the light tan color of a discharge base. CYMK gets muddy if you don't know linearization of your halftone outputs. ie, 20% dot gain when imaged on film and another 20% when you go to print. Dark saturated color and shadows that are mud. Will not work well on colored shirts, teal doesn't discharge well, and printing on a white base with CYMK should be left to the Coudrays of this world.

Sim Process - any color shirt can be printed with simulated process, but you need more screens and some presses in the 6-8 colors should not attempt. This is my favorite as inks are opaque, and if you design your art right you can print all the shirt colors out there in one print run without stopping.

Alan Buffington
Murakami Screen USA

 

[teezecrost]

Thanks, Alan! Just what I was looking for.
So it sounds like I should stick to simulated process for the most part.
I have a 6/4 press. I'm sure I could still do some sim process of limited color-range, no?
PS - do you mix custom colors based on how you seperate your art, or are there specific inks one should seperate for?

 

[Alan Buffington]

Pantone colors are the way to design and separate so your ink department can mix opaque plastisols and save them in a library of little quart containers. INk companies offer pantone matching systems.

In a nutshell here is how we did it;

Illustrator - use only Pantone Solid Coated color numbes to design with.
Photoshop - I have a whole newsletter on this separation method if you want it, but basically you can map your design with the index mode and use those results over a hafltone base. An anagalous color scheme is advised for smaller presses in the 6 color range. All orange yellows and reds with black and white. Within this is a whole world of secondary colors you can get by basing the pantone color back with halftone base to create transparency in the inks, use the color selector tool and the fuzziness slider to spread color.
Thomas Trimingham has made excellent articles on this using curves in photoshop. There are many ways to pull color. Fastest and cheapest for anyone new is to experiment with index color.
Base Plate: 225S 55 line halftone of the white base, original design, greyscale, invert, punch contrast.
Colors: 280-380T depending on stochaistic dot size. Index color mode. Select 2-3 more colors than your press.

email me if you'd like the article on fast sim process separation.

On your press you would be better off with CYMK on designs with lots of different colors. You have an advantage over autos, you can flash each color. If discharge you can go wet onto wet, if plastisol you can flash in between colors. Black may not be necessary here if the sep and art work with just CYM, avoids the muddiness of 4/C process.

[email protected]

 

[teezecrost]

Thanks again, Alan.
I'll email you for that info right away. You're not talking about doing actual index seps, are you? We're still talking sim. process? From what I hear, index requires VERY tight registration, and many colors.(?)

 

[Alan Buffington]

Index and sim are one in the same to me. I can take index back to halftones for the sim process look.
Both require dot on dot registration capability. No halftones? Spot Color. Actually index does not need as tight a registration as you would think as the ink builds up and melts and any slight movement is not noticed unless its in a 'reference' area like lettering that we can see the out of register easier.

 

[sben763]

Rob all is great advise but I use a simulated process separation, I run a 5 color plus white on most jobs. Yes there is times I need more or I can combine a channel if the customer oks it. I do not do any CYMK at least not for the last 2 years. When I did I would separate then tone down the black channel with the curve tool to prevent the muddy look. I just prefer simulated over CMYK.

 

[TYGERON]

+1 to all of the above. Another consideration is how accurate your reproduction needs to be. Process color matching can be a very daunting task. Accurate and consistent CMYK work is more often done with additional spot colors to compensate for the limited color gamut. And some printers will use an underbase white even when printing on white. If matching an original isn't too critical, Process can work well especially with limited small press color capability if it looks good as a stand alone image. Very good Index can be done with 6-8 colors (or less) but the more colors, the better the print (can be). A LOT depends on the art being reproduced and, as importantly, the skills and abilities of the separator.
One other thing. When creating an image, how it's going to be printed can determine how the graphic is built and a great deal can be done in the creating stage to MAKE it print well or better with either method.
On discharge...all fabrics/dyes/colors are not created equal and can be all over the place as far as dischargeability. Some darks/blacks will discharge stark white, some tan or yellowish. If done in lieu of a white underbase it's not as critical epsecially if printing opaque/dark top colors. Either way care should be taken when choosing garments for discharge.