If you want to work with letterpress you better understand color and ink. Many factors come into play and it is impossible to cover everything here. Please read on for the basics of letterpress ink on paper.
Seeing in spot colors
Choosing colors for print still involves looking at actual swatches of colors under real light. Ink colors on paper are very different to the hues your fancy Apple computer and their friends at Adobe Illustrator are feeding you. Computers are marvelous at many things but simulating real life color ain’t one of them.
Letterpress is a form of spot color printing where ink is mixed to the specific desired color. This varies from digital printing or offset lithography. Although spot colors can be printed with offset lithography, generally it uses 4-color process where the different colors are created with overlaid screened tints (dot patterns) of cyan, magenta, yellow and black ink (CMYK). A greater number of colors and more subtle variations can be achieved with spot color ink compared to what is possible with 4-color process. And we won’t even mention the pitiful array of colors possible with RGB.
As you’ve probably noticed, letterpress printers don’t like change. So you will often see spot color projects specified as 1/1 or 2/0 or 3/2 and such. 1/1 means 1 ink color front and back, 2/0 would be 2 ink colors on the front side with no printing on the back. 3/2 refers to a very snazzy job with 3 ink colors on one side and 2 on the opposite side. To make things clearer we usually state the number of colors as 1 over 1 or 2 over 0 or 3 over 2 and so on. These descriptions mean the same thing. We don’t like to be too difficult.
Talking about color
If you’ve ever had a conversation with your grandmother about color, you probably understand why color is too abstract to discuss in ordinary words. Granny’s teal may be your turquoise. This is why the graphics business has standards for selecting and specifying colors. This industry standard is the Pantone Matching System.
The jazzy colors you have in your head should be communicated with a Pantone Solid Color Uncoated reference number which can be selected from a handy Pantone swatch book. Nearly all ink colors are custom mixed by hand. This saves us from buying a big can of pre-mixed ink in insipid pink for someone’s baby announcements and having the remainder of the can go hard sitting on the shelf.
The reason an Uncoated reference number is used is because most letterpress jobs are printed on uncoated stocks. Ink colors on uncoated stock are not as dark or bright as colors printed on slick coated stock. Rest assured though, the little vividness you give up is more than made up for with letterpress goodness. The point is, you must refer to a Pantone Uncoated reference to really know the color you are specifying. Looking at a coated swatch is not the same and don’t even think about supplying CMYK percentages or those voodoo HEX numbers.
We take great care and pride in the mixing of colors. However, it is not a totally foolproof process. Colors can shift slightly as they dry or depending on the color of the paper (more on that below). Or, our Pantone book may be slightly different than yours. We take these things into account when preparing the custom ink mix and when the job goes on press and make sure everything is as close to the reference as possible. Please note though that a very slight variance in the color compared to your swatch book is possible.
Opaque it ain’t
Letterpress inks are translucent and certain hues are more transparent than others. Creatively this can be used to great effect when overlapping (overprinting) two different colors. However, keep in mind that any paper color will affect the translucent ink colors. The darker the paper the more it will shift the colors. And you can forget about using most colors on a very dark stock. Learn more about printing on black or dark paper stocks here.
Flood of color
Laying down large areas of ink to create an overall flood of color is another area where litho and letterpress are not the same. If you are looking for an impeccably perfect, smooth and solid-looking flood coverage of color, you would be well advised to seriously consider offset litho instead of letterpress. Lithography is much better for this. Some mottling will inevitably be visible in large areas of coverage with letterpress. Plus the mottling will vary somewhat throughout the run.
Of course mottling is one of the characteristics of letterpress that people like. And this is dandy as long as the designer is aware of it and feels it work with the design.
It often takes two runs through the press to get a fairly solid flood coverage and even then there may still be a bit of mottling here and there. If this is what you are after then great but 2 hits of a single color does cost more and it still will not be as solid as litho.
So the first career altering decision when considering the best form of printing to use for a design is to determine which medium is best to reproduce the look you are after. We don’t do lithography in our shop and have nothing against it. What irks us though is when people send us a quote request for a design that is obviously only going to work with offset litho or digital printing.
Shapes and color
If the last section on floods of color sounded tricky consider this. In order to get a larger shape or flood area of ink coverage to print its best, the press ink flow will likely need to be increased. If your design happens to have very fine or small type right next to a large shape of the same color, increasing the ink could affect the reproduction of the fine type. We understand that design often relies on contrast. Likewise, the designer should understand that relief printing (letterpress) is subject to the laws of nature and under certain circumstances this means reproduction perfection is impossible.
As early as possible before a job goes to press, it is always a good idea to send us at least a rough layout of your design. This gives us the opportunity to discuss any potential issues such as the large shape next to fine type situation described above. Together we may decide that two plates and passes through the press for the color is the solution. This would give much more control over each each distinct element but would cost more. Alternatively, it may be decided that revising the design and artwork is the best option. The point is it’s best to talk, pre-production.
A letterpress piece does not have to be fancy and some of the best work only uses single color printing. If like me your taste is particularly drab then printing with black ink may interest you. You also save a bit of dough when you use black ink compared to special mix Pantone colors. This is because we scoop regular black right out of the can. Oddball blacks such as PMS Black 7 will require a special mix fee.
Who needs ink at all
An inkless blind impression is when the letterpress printing plate is pressed into the paper surface making an indented impression of the image using no ink at all. We will often use varnish or a tonal ink color that is the same as the paper to give this subtle technique just a touch more umph. Please note that inkless blind impressions are charged as custom ink colors because they often take more fiddling to get them to look their best.
NOTE: Blind impressions are similar to but not the same as proper debossing or embossing which are more complicated and intricate processes. We do offer true debossing or embossing if needed at additional cost.
All colors a touch greener
Cranky Pressman printing inks are vegetable based, low VOC (volatile organic compounds) and are more environmentally friendly than old style petroleum based inks. Please note, until new formulas are developed by manufacturer, metallic inks contain oil.