Newbie Color Managment Question

[sakthivels]

Dirst of all a warm greeting to everyone on the forum.

I'm Sakthivel, a amateur freelance designer from Chennai, India. I have a few questions to ask.

I primarily use CorelDraw for creating artworks, I'm new to Illustrator at the moment. I do some small design works for a few clients, for their Business Cards, Logos, invitations etc. I get them printed from a local Xerox Center, these people have Canon 7000 series and Xeron 550 series production printers.

My question is how to i achieve consistent color output when using Pantone Colors. I really like the cool shades from the Pantone Library, I use Goe coated as well as Pantone process swatches in Coreldraw.

For the time being, I'm just tied to hardwired CMYK values, to ensure consistency, but at times this also fails and I have to ask the printer to calibrate and then print, which somewhat gives a better result.

Is there any hard and fast rule for Pantone shades or I have to use some software / hardware to maintain consistency.

Any help of advice is appreciated.

Thanks in Advance,
S. Sakthivel

 

[Amer]

Generally, if you're digitally printing you are better off not using Pantone colors since your artwork is being printed as CMYK anyway. Also you run the risk of Pantone colors being printed differently on different RIPs since some of them use special spot color lookup tables for better reproduction, others don't, those lookup tables differ, printer gamuts are different and so on. You also have to figure out if your application is passing the Pantone colors on or is doing the CMYK conversion itself. Not to mention the fact that Pantone likes to change the color definitions of its colors every couple of years. Also, the majority of those nice cool shades you like so much can't be achieved from CMYK.
So, what can you do?
Try to get a print provider who regularly calibrates his equipment and prints consistently, while you yourself stick with colors that are possible to get on digital equipment.
Or, if you're doing a larger run, print it the traditional offset way with true spot colors and you'll see the difference.

 

[thomaus]

On our iGen and Colorpress printers we find truer reproduction when the Pantone colours are left as spots in the application or PDFs. Inside the RIP, the colours get reproduced using the lookup table for that printer. This uses the wider gamut available than the standard CMYK mixes, and can be a better match much of the time. This is an option that can be turned on or off in the Xerox RIPs. We leave it on.

Depends on your service provider and how the equipment is set up.

 

[Correct Color]

You're asking question for which the answer depends a great deal on your situation, but just a couple points...

For the time being, I'm just tied to hardwired CMYK values, to ensure consistency...

You're actually doing exactly the opposite of ensuring consistency by going this route. Because there are no definitive CMYK values for any PMS color. All CMYK values are device dependent, and Pantone has actually never shared with the world exactly what CMYK space they used to make their conversions, so there's no way those values can equal the color you're seeking in your final print space.

Also you run the risk of Pantone colors being printed differently on different RIPs since some of them use special spot color lookup tables for better reproduction, others don't, those lookup tables differ, printer gamuts are different and so on. You also have to figure out if your application is passing the Pantone colors on or is doing the CMYK conversion itself. Not to mention the fact that Pantone likes to change the color definitions of its colors every couple of years.

Most of that is kind of widely accepted as true, but in reality, it's not.

Pantone sells the same libraries to everyone, be they RIP manufacturers or Adobe or Corel Draw or whomever. And all of them are the same, and boil down to a bunch of names, with associated L*a*b* values. Assuming you name your spot color correctly, the RIP will in all cases be looking for the same L*a*b* value in the destination print space.

Also, most applications send spot colors out as L*a*b*. Even Adobe, which for years displayed them as if they were CMYK, processes them through as L*a*b*. It is true that it's fairly easy to lose spots creating a pdf, but that's an error in pdf generation settings, not the application itself.

And, finally, Pantone really doesn't change their definitions every few years. In fact, while they're added new colors over the years, the original base ink formulations for all their colors have never changed.

Awhile back, when they came out with the -- in my opinion -- ill-advised "Plus" "update", they did change the stock on which they print the books, and this change led to some L*a*b* values of many of the old colors shifting a bit.

However, unless you're printing on the exact same stock as the books, the difference between your stock and the book will render the difference pretty much moot.

Bottom line: Call for PMS C colors in all cases in your artwork; if you generate pdf's, make sure they retain spots as spots; and find a printer that understands how to print your artwork correctly.


Mike Adams
Correct Color

 

[Stephen Marsh]

Dirst of all a warm greeting to everyone on the forum.
...these people have Canon 7000 series and Xeron 550 series production printers.

My question is how to i achieve consistent color output when using Pantone Colors. I really like the cool shades from the Pantone Library, I use Goe coated as well as Pantone process swatches in Coreldraw.

Sakthivel, these type of machines are famous for their drift, device colour is generally far from stable (thus spots will be off too). One calibration to the next may deliver quite different tone and colour. So whether you define colours in RGB, CMYK or as true named Spot colours that are then used for a Lab colour lookup table at the RIP - colour may be all over the place. If the digital shop is great, then their output will be consistent (to be fair, it is often more about the print technology than the shop being good). In my experience, it is neutrals and lighter tints and pastels that are usually really hard to maintain, while saturated colours show shifts to a lesser degree.

If a certain colour is critical, then I would go in person on the day of printing, get them to run out a sample on the final stock with whatever settings will be used for production and adjust the colour to print as required if it is off...then hold your breath and hope that when the job is run the colour is the same as the test proof. Sign off for colour on this sample and get them to check colour throughout the print run to ensure that it does not vary too much.


Stephen Marsh