FM Screens, Hexachrome, and Other Fun Printing Stuff
The world of print is not made up entirely of cyan, magenta, yellow, and black inks printed in a regular grid of halftone spots. Sure, that’s all good for most printing, but sometimes — when you want to optimize the quality of your print materials — you need to wander outside the box and play with different technologies.
FM Screening
For example, I’ve been a fan of FM (frequency-modulated) halftone screening for almost two decades. FM screening — also called stochastic screening — is a way to print a tint of a color more like an inkjet than a traditional halftone. That is, instead of a regular grid of spots that get bigger (in darker areas) or smaller (in lighter areas), you make a bunch of tiny spots closer together in darker areas and farther apart in lighter areas. And, just as inkjet printers can create photo-realistic images better than a traditional printing press, FM screens can express more detail (and even do so with lower-resolution images than traditional AM screens).
There has been a great deal of debate over the past decade about FM vs. AM screening, but the problem is that much of the commentary seems to come from people working at RIP manufacturers. In other words, they’re not always the most unbiased of observers. The main argument against FM screening has been that it’s difficult to manage on press. However, many people report the opposite — especially in direct to press and digital printing situations, FM screening can be a very viable option. Plus, you never have to worry about moire patterns!
While FM screening shows up in some platesetter RIPs, there is one third-party option that I think every printer (and possibly designer) should know about, which is Icefields from ISIS Imaging. The ability to create your own FM-screened images means that you can specify how each image on your page is screened. For example, in a magazine about gardening, there may be one image on each page that needs to just exude quality and detail. The other images and background tints could be traditionally screened. Use Icefields on that one image! It’s certainly worth checking out, especially if you’re a output provider.
Hexachrome
While FM screening can make your colors pop better, another option is to print your images with more than just four colors. For example, you could create a bump plate with a single spot color to help bring out a special color. Another option is to use hexachrome printing — a 6-color solution originally created by Pantone.
While QuarkXPress has had support for hexachrome for many years, InDesign doesn’t offer built-in support for it. Fortunately, I saw this nice article by Brian Lawler about how to use Photoshop CS4 to convert RGB to hexachrome. I’ve seen a number of other hexachrome-related posts on the web, too, including this one.
Are there other technologies out there that you’ve used? Other fun ideas to help enhance print jobs?
The issue with FM screening is that depending on the color build you are using the color can look mottled or pixelated.
Alternating varnishes is another very nice way to pump up your print job. You can have your printer lay down a spot matte varnish and a spot gloss varnish to really add depth to your page.
@Eric: I have seen some mottling when FM is used for solid color tints (like flat color backgrounds or gradients). That’s why I prefer Icefields’ just-the-images-you-want approach.
David, I dig super-techy stuff like this, too! Alas, I’ve not yet been able to produce any print jobs here in Norway with FM screens, even though I see some local magazines are using it.
Years ago, I experimented with various arcane processes in Photoshop to create my own FM screening. I had it working fine for some kinds of images, those which had many tight textures, but smooth gradations were troublesome with my home-grown procedures.
On clicking your Icefields link . . . I find it’s Mac-only! I hate it when you Macnoids send us Windows folks on wild goose chases like that. Please give a Mac-only/Win-only alert in all postings, when such restrictions apply.
We print a three-volume book that contains nearly a thousand graphs, and, to keep the bar and line colors in the graphs consistent, we use 5 spot colors instead of CMYK. But that has made for some serious moiré patterns in our other images. So last year we and our printer decided, after much discussion, to print the entire book with stochastic screening, It worked great. We did have some mottling on our solid backgrounds (happily, it was in visual elements that ended up looking fine with a bit of subtle texture to them), but everything else was perfect. The photographs had amazing clarity?noticeably better than with AM screening. And though the press foreman was initially quite hesitant (he insisted on running a form with a set of traditional AM plates, so we could see the two side-by-side before we committed), I think he and the press guys ended up very supportive of the whole thing, and didn?t seem to have any difficulty managing it on press.
In addition to AM and FM screening there is another one out there that uses the best of both worlds. It is a Hybrid screening, which helps to eliminate the mottling that happens.
There can be problems with FM screening if you are trying to use a very small micron dot when creating plates on the Platesetters, such as a 20 micron dot. Some platesetters/plates have problems holding dots that small.
I have been printing with FM screening for years. 10 micron on coated and 20 micron on uncoated. The results are fantastic and I have had almost no mottling on solid colours. In fact most solids look like they were printed as spots.
The only thing is make sure your calibration is good and that your printer produces accurate proofs. Unlike AM screening FM is almost impossible to adjust on press.