Accurate color in digital printing is something I’ve been passionate about for years. I’ve taught classes on it, trained numerous people in it and have done countless hours of testing and experimentation with printers of all types.
Because accurate color should be expected wherever you do your printing, yet so often print service providers neglect it. When John Swaney gave me the opportunity to head-up his printing operation here at Precision Signs & Imaging, one of the things I was most excited about and that we both agreed upon was that our color capabilities had to be outstanding. Heck, “precision” is in the name of the company so we had to be able to hit colors!
Today I decided to write a bit about color science and how perfect color is achieved from the perspective of a self-proclaimed color nerd.
I put a lot of work into making sure our equipment produces tremendous color, but it doesn’t end there. I not only want my prints to look amazing, I want them to be repeatable 6 weeks, 6 months, or 6 years down the road. If a customer comes back to me at a later date wanting a replacement sign, for instance- I need to be able to give them exactly what they got last time. Maybe a customer bought a sign from us and returns to us months later to wrap their vehicle- I want their logo colors to match no matter what we’re printing on. That same customer could come back 2 years later with a fleet of vehicles they want to wrap the same way as their first one. If so, I’ll make that whole fleet match and look great together. So the key for me has always been to make it look great on every type of media, and make it repeatable.
I accomplish this by first measuring the ink output of our printer to lay down as much ink as a given media can handle without the ink pooling or running off- the sweet spot. Next, I linearize the printer to ensure that the machine can print gradients evenly from 1% to 100% for each printhead in the machine so the transitions from light to dark areas will look great. Once all of this is done I create the most important color weapon in my arsenal- the ICC profile. I print out a collection of various color swatches, typically a couple hundred, which are then measured with a spectrophotometer- which is a fancy word for a very accurate color scanner. It reads these swatches and measures the way light bounces off of them and turning color into a set of numbers. These measurements for all of the colors I printed become a data set which I compile into the ICC profile.
Once I’ve got this profile, my computer knows EXACTLY what colors my printer can produce on this specific media. If I print an image using this profile, the computer will look at the colors in the image and compare it to the colors the printer is physically capable of reproducing. It then will adjust the image to get the very best representation possible on that media. Furthermore, if there are Pantone colors in the document my software will automatically find the nearest scientific match for that color. Cool huh?
If you think all of that work sounds tedious, it doesn’t stop there! This profiling process needs to be done for each media, at each resolution. It’s a lot of work, but once it’s done the benefits are huge. My customers just know their prints look awesome, but I know I can deliver that awesomeness again and again at the drop of a hat. Most of our colleagues in the industry don’t employ this technology because of the effort required, but I feel strongly that it sets us apart and allows us to deliver color they can only dream of.