Monitor calibration for Spot colors

[scorley22]

We do a lot of packaging design work and our timelines are really tight most of the time... This is a problem that we are running into quite a bit and I am looking for a solution that would work for our small studio. And let me start off by saying that I am not exactly a real technical person and don't have a huge background in pre-press and production. I am not looking for someone to talk over my head with a solution. Pretend you are talking to a student

Using this current example to illustrate what our problem is:

We are working on a line of packaging for a food brand. There are 12 different flavors of this particular product. Using the same layout (look and feel) for the product line and using a different color palette for each sku to differentiate flavors. We have the ability to use 4 color process and 2 spots on each package. We have 3 designers that might be working on the same project at any given time and each one has a different monitor.

Our problem doesn't come when we are going into final production... we get physical color proofs/etc. That's not the problem. The problem lies in the actual design process. I can look at a swatch book all day long and pick colors that I think might work the best. But it doesn't really work with our rapid pace workflow to use a swatch book when we are exploring color combinations that work with the rest of the line up of products. Seeing a better representation of what a spot color will look like on screen would help dramatically for our design process. Obviously PMS colors don't show up on our screens as a WYSIWYG type of thing and we can get drastically different results on a color proof from the printer than what we have chosen on screen and what our clients have seen on screen.

Is there anything (a color profile, software, calibration tool, etc) that could help us get a better (not perfect) result in the design process as far as color representation on screen?

I have seen things like this or this but don't know if they would do the trick?

Thoughts?

[Ton Frederiks]

You are on the right way with thinking about a calibrator.

But you also need a monitor capable of displaying Pantone colors.

I think a monitor able to display AdobeRGB instead of consumer sRGB comes closer to display spot colors when correctly calibrated.

[scorley22]

Yeah, I have a BenQ PD3220U Display... my other guys have apple monitors/imacs

[Ton Frederiks]

Use color management.

Calibrate that monitor and avoid colors in your working environment surrounding that could influence your screen.

Don't expect a perfect match, there will always be colors that can be displayed and not printed and colors that can be printed but not displayed.

[scorley22]

What do you mean when you say "use color management"?

[Ton Frederiks]

Set up your Color Settings correctly, calibrate your system, use the right profiles.

[scorley22]

I am running Adobe RGB 1998

[Mike_Gondek]

Get yourself a hardware calibrator as per you links, would recommend not going through pantone though. The calibrator will be a big  help, but never 100% perfect, some monitors are better than others and the RGB spaces monitor can represent some colors very accurately and other not so close when they fall out of the monitor gamut.

PIcking the right color combinations in packaging design comes with time and remembering experiences with colors used in the past. Being able to look at the printed swatch book is important and going to a viewing booth and laying the swatches on top of each other.

Try asking your printer for a proof earlier in the process or ink drawdowns?

[Test Screen Name]

Every spot colour in your apps has an "alternate colour". It might be CMYK, RGB or Lab. It will show on screen EXACTLY as it would if you had designed with that CMYK, RGB or Lab colour.

So you have multiple issues to address

1. Where do the alternate colours come from? From a swatch library supplied by the ink maker? From something you type in?

2. Can the colour actually BE represented in the colour space? For instance, a bright blue that can't be printed in CMYK also won't show on screen if the alternate colour is just CMYK. Lab is recommended, Pantone moved to it a few years ago. But it won't give realistic simulations of special effects like metallics.

3. If you are mixing inks rather than using a pure tone, you are getting into very complex territory. Inks mix in different ways, and the order of printing is a major factor in some cases.

[Ton Frederiks]

And don't forget to always use Overprint Preview when looking at Pantone Spot colors.

Overprint Preview will use the Lab values instead of the CMYK simulation to calculate the screen display.

[JETalmage]

scorely22,

Monitor calibration devices can assist you in making your shop's various monitors look similar. But it really can't address the root issue:

First, understand: No matter what the color model of your document is, no matter how painstaking your calibration, all your monitor ever displays is an array of glowing RGB pixels. It is simply unrealistic to expect a glowing RGB monitor to accurately display the appearance of physical, reflective spot inks because there is more to it than just "color."

The above-mentioned example of metallic spot inks is classic for explanation purposes. The defining difference about metallic inks is that it has the reflective sheen properties of metal. You can mimic the appearance of metallic surfaces in artwork by actually drawing reflections, but that does not translate to a single color separation. No combination of RGB values is going to mimic that appearance.

You can prove that to yourself:

1. Take the physical Pantone swatch book for metallic spot inks to your computer.
2. Select any metallic ink swatch. For example, a "rusty bronze" metallic.
3. Use the software's color mixer to define a color that looks as close to the physical swatch as you can.

No matter what you do, the closest you will get is a muddy dark orange that simply does not look metallic at all. No one looking at that color on your or their monitor will perceive it as the appearance of a metallic ink. It's just not going to happen.

The same principle applies to far more spot inks than just the extreme example of metallic inks. A familiar everyday example is school bus yellow paint. Color-wise, it's an orange. That implies some combination of Y and M in CMYK, or some combination of R and G in RGB. But no such combination really matches it, because that industry-standard paint has a luminance and chroma that just can't be mimicked on an RGB computer monitor.

That, in a nutshell, is one of the reasons why spot inks exist in the first place. And it's why we still use physical swatch sample books when designing with spot inks.

Now as far as your shop's workflow is concerned, understand this: In software, a spot color is nothing but a command to send objects colored with a particular swatch name to a separate grayscale separation plate. That's it. There's really no "color" involved. Just think of a spot color as an instruction to the print shop to load the press's inkwell with a particular industry-standardized physical ink.

That means that you can literally specify any "color" mix you want for displaying a spot color swatch in your software. You do not have to use, for example, Pantone's recommended color mix for displaying, say, Pantone 124. You can just create a new Spot Swatch, name it "Pantone 124", and with the physical Pantone swatch book in hand, adjust the RGB or CMYK sliders however makes the best "match" to your or your customer's eye. It won't make any difference whatsoever in the actual print, because that's simply a matter of the pressman loading Pantone 124 ink into the inkwell.

So if your shop has a set of repeatedly-used spot inks for particular clients, you can standardize the display values for those spot inks within the scope of your shop by defining those Spot Swatches, saving them as a Swatch Library, and making it a business rule for all your designers to use that Library for spot color projects.

By the way, I'll differ with Ton on this: Do not use Overprint Preview when working with spot colors. Illustrator's Overprint Preview assumes the translucency of CMYK process inks. One of the many differences of spot inks is that they are quite often more opaque than process inks.Illustrator (at least as of version CS6) provides no adjustment of opacity when defining a Spot Swatch. Therefore, for example, with Overprint Preview turned on, a spot ink that is lighter than the inks behind it will always look darker in the overlap areas, when it should look lighter.

JET

[Ton Frederiks]

JETalmage  wrote

By the way, I'll differ with Ton on this: Do not use Overprint Preview when working with spot colors. Illustrator's Overprint Preview assumes the translucency of CMYK process inks. One of the many differences of spot inks is that they are quite often more opaque than process inks.Illustrator (at least as of version CS6) provides no adjustment of opacity when defining a Spot Swatch. Therefore, for example, with Overprint Preview turned on, a spot ink that is lighter than the inks behind it will always look darker in the overlap areas, when it should look lighter.

I agree with a lot of the arguments made that some of the spot colors are difficult or impossible to reproduce on screen.

But the Overprint preview does a better job, it uses the Lab values instead of the CMYK simulation used in normal Preview.

It does not mean that you have to set the spot to overprint to get this better preview.

Have a look at these screendumps and read what Mordy Golding wrote about it (in 2007):

Real World Illustrator: Busting the Myth: achieving consistent color across Photoshop, Illustrator, ...

[JETalmage]

I understand your argument, Ton. But advising users to "…always use Overprint Preview when looking at Pantone Spot colors" is too general, and therefore bad advice, especially for someone who even stressed: "I am not looking for someone to talk over my head with a solution."

We should be careful making admonitions like "always use." There are always exceptions, and I dare say in the context of spot color, the exceptions are more common than your recommended "rule."

Scorely22 specifically mentioned he is setting up process-plus-two projects, not one- or two-color spot jobs. It's quite likely—I'd even say probable—that the two spot inks will be set to overprint process inks, if only for trapping. If they are, Overprint Preview will wreck the on-screen appearance, especially for the purpose of customer soft-approval.

Also, I will reiterate my previous point that '…all your monitor ever displays is an array of glowing RGB pixels…'. Scorely22 needs to understand that's still true, even if those RGB values are converted from Lab values. He's still looking at RGB, not spot inks.

A large reason many garment imprint designers default to multi-channel format in a raster program for higher quality imprint artwork is because opacity can be set for each channel, thereby far more realistically simulating the printed results. I've long argued that the setup for Spot Swatches should include an opacity setting. That would make Overprint Preview far more useful for projects involving spot inks.

JET

[Ton Frederiks]

JETalmage  wrote

I understand your argument, Ton. But advising users to "…always use Overprint Preview when looking at Pantone Spot colors" is too general, and therefore bad advice, especially for someone who even stressed: "I am not looking for someone to talk over my head with a solution."

We should be careful making admonitions like "always use." There are always exceptions, and I dare say in the context of spot color, the exceptions are more common than your recommended "rule."

This comes from your first reaction:

Do not use Overprint Preview when working with spot colors.

That does sound as a very general advice to me.

I think that using Overprint Preview is a good habit, it gives a better representation of the spot colors and shows the interaction of inks if Overprint is applied. Without Overprint preview, the Overprint would be invisible, it is like working in the dark and could cause costly mistakes.

I agree that the preview is not perfect as long as ink opacity information is not included in the Spot color, but there is work going on by ISO to communicate measurement data for spot inks. So there is hope for the future.