Part 2 of Our Virtual Convention Table
This is part two of a four-part series about our graphic novel, Meow the Infinite. Part one was about how we, a game R&D company, ended up doing a comic in the first place. Part three covers Anna’s drawing process.
It’s crazy how much work goes into a printed graphic novel. Assuming you started from a set of RGB Photoshop files for a digital comic, it’s tempting to assume that you just hand it to a printer and out comes a beautifully printed book.
To some extent that’s not entirely untrue. If you want to have a print shop do all the prepress work for you, you can try
handing them an untouched set of Photoshop files and cross your fingers. You might luck out and pick a great shop that will catch all your mistakes, and if you don’t mind that some things won’t come out exactly the way you might’ve wanted, then that’s probably good enough.
But good enough isn’t great
If you actually want to make smart decisions and provide high-quality starting materials for your printer, there’s a ton
of details about the print process you should know.
I knew almost none of them when we started work on Meow the Infinite
. But as we went through the prepress process, I found myself fascinated by everything there was to learn about printing.
As part of our Kickstarter
, I recently did a livestream where I attempted to recount all of the things I’d learned about printing (along with some things I already knew, having been a graphics programmer for several decades). You can check out the entire thing, broken up into topics, on YouTube:
Since video isn’t everyone’s jam, what follows is a long-form companion piece that tries to touch on everything you need to know about printing if you want to understand the prepress process.
Let’s start with how you get from the screen to the page in terms of literal ink on paper.
A modern monitor typically has an LCD or OLED panel. Each pixel is an element that can vary the intensity of red, green and blue light shining from that location. Inside Photoshop, when you’re picking a color, what you’re really doing is controlling those three emission levels. It can get a little more complicated (especially with LCDs), since there can be non-uniform backlighting and other cross-pixel effects depending on the monitor. But at the end of the day, picking red, green, and blue intensities is what you’re doing.
By default, these intensities won’t really correspond to anything specific. This is especially true if you have a monitor you bought randomly and left on the default settings. With that setup, you’re really just playing around with these values to make colors that look good on your
monitor. You have no idea what that actually means or corresponds to in the real world.
Close-up of an LCD monitor displaying a panel of Meow the Infinite. Note the individual pixel elements are clearly visible, even without a macro lens.
Even if you aren’t doing print work, you may have experienced problems related to this. When you save an image and load it up on someone else’s monitor, or your laptop, or on your phone, you may have noticed it can look quite different! It might be higher contrast, or more saturated, or have any number of other subtle differences in apparent lighting.
This happens because most monitors are just displaying colors by taking the values coming out of Photoshop and mapping them to a range between the darkest and brightest lighting the monitor can produce. The average monitor isn’t trying to match any kind of reference spectrum, it just has some factory settings designed to make it look as impressive as possible when viewed in a row of monitors at your local AV superstore.
So the first thing that you need to do if you want to be serious about print work is to get serious about screen
To do that, you need a color-calibrated monitor. You need your monitor to adhere to some specific reference color profile, so that when in Photoshop you set the color to 170, 33, 49 for RGB, a very specific color comes out of that monitor. It’s not because that’s going to give you a better image than what you previously had with a random, uncalibrated monitor. It’s that now those numbers mean something specific to the world outside that particular display.
To color-calibrate your environment properly, you need to not only have a monitor that is calibrated to a specific color profile, but you also need to tell your operating system and software which profile that is
. Thankfully, there are international standards for this that are now ubiquitous: they’re called ICC color profiles
An ICC color profile is a standard way to describe what specific color values should look like in the real world in terms of the light that you will actually see. If you calibrate a monitor to an ICC color profile, and tell your software what profile you used, it can then adjust the way it displays your artwork such that the colors will look the same on any other
properly calibrated system.
Now, you can buy a special device that you can use to calibrate any monitor as closely as possible given the quality of the monitor. But that’s definitely the hard route. If you’re really
into color accuracy, it’s probably the best way to go, but there’s an easier route for most users.
The easy route is to just buy a factory-calibrated monitor
. In the old days, that was a bit of a luxury, but these days it is extremely easy to find an inexpensive monitor that’s factory calibrated and can be set to a known ICC color profile (like sRGB). At Molly Rocket
, we all have an inexpensive HP Dreamcolor display as a second monitor on our desks that we use specifically so everyone can see the same colors when color grading (eventually we’ll have to switch to HDR reference monitors everywhere, but we haven’t made that leap yet.)
The reason that you care about all this for prepress work is because once you want to take an image on a screen and turn it into ink on a page, you need some way of figuring out what ink to use, and how much. Well, the exact same idea — that you should calibrate your work to a known ICC color profile — can be applied to inks and paper. And if the monitor is calibrated, and the press
is calibrated, then you can actually get a reasonable preview of what colors the press will actually print without ever actually printing
This sort of previewing is why there are color profile settings in art packages.
Here are the ones from Photoshop:
The color profile selections in the “Working Spaces” box tells Photoshop which ICC color profiles your RGB and CMYK files should use by default. Picking the correct profile setting for RGB is easy: you can just match the color profile listed in your monitor’s settings. On our monitors, for example, you can actually pick from several in a menu — sRGB, Adobe sRGB, BT.709, etc. Note that this isn’t
actually setting the color profile Photoshop will use to output to your monitor! This is just setting which color profile you want to work in when using RGB images, so technically you can pick anything you want, but it makes sense to pick a profile that your monitor can actually display.
Picking the correct profile settings for CMYK work is harder, because it doesn’t depend on your
setup, it depends on the print shop’s
setup. In order to select the right profile, you’ll need to ask them what ICC color profile you should set. And that’s something you have to do before
you start prepress.
Of course, this isn’t always possible. If you’re on a tight schedule, it may be that you have to start prepress work before you know which press is printing your book. In that case, a reasonable solution is to pick any common print ICC color profile (of which there are a few). It may not be exactly right, but it will be close. When you do eventually pick a printer, they’ll take the files in the temporary color profile and translate those colors into their actual
But then there is the question of what Photoshop thinks the monitor
profile is, a setting which mysteriously doesn’t seem to exist.
The “Working Spaces” dialog sets the color profiles for your images
, but obviously Photoshop can’t know how to display those properly without knowing what color profile the monitor is calibrated to. So why isn’t there a setting for that?
There’s no setting in Photoshop because Photoshop always uses the operating system
to determine the monitor color profile. So whatever color profile you have set in your operating system, that’s what Photoshop will use.
By default, this is sRGB on Windows machines, but you can check it by going to the Color Management section for the monitor in the Windows control panel. Mine looks like this:
We don’t use Apple computers at Molly Rocket
, but presumably there is a similar setting in the Mac OS X settings for monitors.
If you set or calibrate your monitor to a color profile other
than sRGB, which is the current operating system default, then you also
need to make sure that the operating system
setting is changed to that
It’s overly complicated, unfortunately. But the good news is, if you do buy a factory-calibrated sRGB monitor and set it to sRGB in the settings, then the Windows defaults will automatically be right, and so will Photoshop’s RGB workspace. So the only
thing you’ll have to worry about is making sure the CMYK setting is set correctly.
This brings us to the first major step of the prepress process: translating pages from RGB to CMYK.
Or, if you’re planning for print right from the beginning, you can instead think of this section as how to make
pages in CMYK to begin with. But what exactly is
CMYK, and why is it necessary?
CMYK is just an acronym for the inks the print shop is going to use in a standard print process. The “C” is “cyan” ink, the “M” is “magenta” ink, the “Y” is “yellow” ink, and the “K” is “black” ink. You might think black should be “B”, but of course RGB and CMYK want to be clear about what they stand for, so the “B” was already taken for “blue”.
Now you may ask, why are there four
colors now instead of three, and why those
four? Why not red, green, and blue ink?
Monitors use RGB because the human eye perceives color in a very indirect way. We actually don’t have very good color perception. It depends on what you’re comparing us to, but given that there is an entire rainbow worth of colors we “see”, it is odd to stop and realize that the human eye only actually has three different types of “detectors” for light: one centered around red, one around green, and one around blue.
To a first approximation, our eyes take what amounts to three “color filtered” pictures of the world — one reddish, one greenish, one blueish — and then our brain tries to guess what color everything is by combining the three. This means we can’t tell the difference between something that is shining pure yellow light from something that’s shining a combination of red and green light. Those are actually different things
in the real world, but to our eye, they will look the same.
The canonical human eye spectral response curves, as depicted on Wikipedia. S, M, and L correspond to the three light detectors we have.
So when we build computer monitors, we don’t need to reproduce all the wavelengths of light that occur in the real world. We don’t ever have to produce real
yellow light. Instead, we can just produce red and green light together, and your brain won’t know the difference between that and a true yellow light.
Amusingly, there are
animals that could
tell. Birds for example, often have more than three types of color receptor in their eyes. There are undoubtedly birds out there who would think our monitors look absolutely terrible when reproducing images of the real world!
Printing, of course, is a bit different. Unlike a monitor, when you’re printing, you’re not emitting any light at all. A printed page is just a piece of paper that started off reflecting most wavelengths of light — it was roughly white. If you now want to put color on it, what you’re actually doing is dyeing the paper so it absorbs
certain colors of light and reflects the remainder.
So with printing, you’re not emitting any light at all. You’re removing
light in a controlled way.
In order to reproduce all of the different colors we can see, instead of adding
red, green, and blue like a monitor, the printing process is subtracting
red, green, and blue. That’s where we get the colors cyan, magenta, and yellow: cyan ink reflects everything but
red. Magenta ink reflects everything but
green. Yellow ink reflects everything but
Using these three inks, printing a specific color is similar to balancing the three emitters on a monitor. You’re trying to dial in an amount of three different components in order to get the color you want. But instead of adding up red, green, and blue, you’re subtracting away red, green, and blue by applying cyan, magenta, and yellow ink. The paper’s getting darker
the more you add, not brighter
Close-up photograph of a printed comic panel. Note that unlike the pixels on an LCD, the ink pattern (called "halftoning") isn't clearly visible without a macro lens, although some of the pattern is discernible in certain regions.
You may now be wondering, what about the fourth channel? Why do we have black ink? With RGB, if we want black or white or gray, we just put all the channels at the same level. We don’t need a fourth channel just for grayscale.
So why is RGB just RGB but CMY has to be CMYK?
The answer is fourfold.
First, especially in an “offset” press (which lays down ink sequentially), producing gray or black with only CMY inks means that you have to ink the pages with precise
alignment. If you don’t, the part you tried to make black will actually have a little bit of colored fringing around the edges.
Second, unlike other CMY combinations that might also suffer from that problem, black and gray are very
common colors in printing. Most text is typeset in dark gray or black, so having a separate black ink has the potential to save money. Especially in a book that has large amounts of black text on a white background, you’d much rather pay for just one ink than three
Third, a combination of CMY inks doesn’t produce as nice a black as actual black ink. Again, this would be true for any combination color, but black is much more common that any other combination color.
Fourth, and most importantly for the graphic novel prepress process, black ink gives you another way to control the color reproduction on a page, and allows you to make controlled decisions about the practical effects of the ink and paper.
Since you’ll have to make this decision on just about every page of a graphic novel, let’s talk about it first.
Starting with an automatic translation from RGB into CMYK, the first thing you need to do is assign proper blacks.
You may have heard the terms flat black
and rich black
before. These are the two ways black can be set using CMYK inks. “Flat black” means no cyan, no magenta, no yellow. Just black ink. It’s CMY at zero, with the K channel being the only non-zero value. “Rich black” means black ink plus
an “undercoat” of cyan, magenta, and yellow ink. It’s not full CMY at 100%, because that would probably oversaturate the paper. But it’s some
CMY, somewhere around 50% of each, or something similar. Again, this depends on the print process.
Deciding between the two is relatively simple. Flat black has a duller appearance because it’s just the black ink on the page. The more ink that you put on the paper, the less light it will reflect, so if you just
put the maximum coverage of black ink, but no other ink, there’s still headroom there, because you can only transfer so much ink using a single plate on one pass.
Rich black, on the other hand, uses the fact that multiple plates can transfer more total ink in a single pass. You’re adding as much total CMYK as you reasonably can, for the absolute least amount of reflected light you can get.
By default, if you’re using Photoshop, it will assign rich
black to most black areas of your pages when it does an automatic conversion. So what you want to do is go through all of your images and isolate the layers that you don’t
want to be rich black and remove
the CMY components from these areas.
Which areas are those? Well, as I already mentioned when talking about why there is black ink in the first place, rich black doesn’t work well in places that are thin and high constrast, like small black text on a white background. This is very common in graphic novels, since most text bubbles are black-on-white or close to it.
Original on the left, automatic CMY channels in the center, CMY channels on the right with text bubbles manually removed to ensure they will be typeset as "flat black".
If you leave things like text bubbles as rich black, you run the risk of having slight color bleed on the edges of the font. Forcing them to only
use black ink removes any possibility of chromatic abberration, since the other ink plates won’t touch the text at all.
Furthermore, large black regions, like solid backgrounds, usually want to be flat black because rich black costs more to print (since it uses more total ink), and simple solid backgrounds usually don’t need to be extra deep black. However, to underscore the problems with automatic conversion, this is entirely the artist’s discretion. For some backgrounds, having the deepest possible black may be important.
Changing rich black to flat black was such a common thing Anna had to do during prepress that I actually made a special levels adjustment preset that zeroes CMY and scales K automatically. If you’re doing this kind of work, I highly
recommend making one!
After assigning proper blacks, the next step is to fix gamut problems.
Unfortunately, inks are not as good at reproducing colors as modern monitors, especially HDR monitors. CMYK inks can’t do fluorescent colors very well. Flourescent greens and blues tend to wash out. A computer monitor can easily create all kinds of glowy green and blue colors, but CMYK inks just can’t.
Original RGB on the left, CMYK on the right. Note the fade in flourescent colors on the spiderbeast in the upper left corner.
When you find a page with color problems, there may be subtle tweaks you can do to fix it. But it may also be that you need to fundamentally rework that part of the page. If it relied heavily on neon or flourescent colors, you may have to tone them down and redraw or rebalance an entire image section to restore the original intent of the artwork.
Original RGB on the left, automatic CMYK in the middle, manually-adjusted CMYK on the right. Note the adjustment in the unicorn's legs and horn to compensate for the restricted CMYK gamut.
Once you’ve fixed all your CMYK color errors, and properly assigned flat and rich black everywhere, you’ve probably done everything you need to do to get the interior of your book in order. But what about the cover?
Before you can even lay out the cover, you need to make some choices about paper.
And not just for the cover! Your paper choice for the interior
of the book actually determines the layout
of the cover, because the thicker the interior paper, the longer the spine has to be, which affects the width of the cover image!
But I’m jumping ahead. Back to paper stock. Paper stock varies both by weight and by preliminary coating.
The “weight” of paper stock is a term that indicates how thick the paper is and how it bends, but technically it really is just a measurement of the weight of the paper. “Eighty pound paper” is paper that weighs eighty pounds!
Of course, no single sheet of paper weighs eighty pounds. The unit of measurement is specified to be the weight of the uncut paper in some standard stack size (usually one ream, which is 500 sheets in the US). This is interesting as an aside, but it doesn’t really help anyone intuit
what kind of paper they want.
help is to know that 80lb paper is somewhere around the average weight of a graphic novel page. Heavier paper is usually thicker and stiffer. Lighter paper is usually thinner and floppier.
Additionally, regardless of weight, the kind of paper stock used in graphic novel printing is coated
. Uncoated paper is paper that is literally just paper with nothing applied prior to inking. Matte
paper is paper that has had a small amount of reflective coating applied. Satin
paper has had more. Glossy
paper’s had the most.
To be honest, I’m still a little bit hazy on paper coatings. Terms get thrown around a lot
on these things, and learning them only in passing is not really sufficient. There’s a lot of subtleties, because how the ink interacts with the paper has a lot to do with what coating it had before you put the ink on. This is, for example, where the term “dot gain” comes from: it’s a measure of how much an inked region expands
on the paper.
But thankfully, learning all the technical details isn’t absolutely necessary for choosing paper.
The best way to select what kind of paper you want for your print job is to look at samples from your printer. You can see
how it looks, and you can see how it behaves.
This is going to be a theme for the rest of the article. I’m going to say it a lot. Everything I’m talking about here is a tangible, physical thing that you have to see, touch, and manipulate to really get a feel for what it is. Thankfully, printers already know that, and in my experience are always more than happy to provide you with sample materials so you don’t have to guess.
I can tell you basic facts, like stock with less coating means a duller appearance and less glare, while stock with more coating has a richer appearance but more glare. But the best way to pick a page weight and coating is simple: play with the samples and see which one you like better!
Unless you are doing something very fancy of your book, picking a paper weight and matte/satin/glossy is probably all you’ll need to do for the interior. Not so when it comes to the cover.
While technically there is no real difference between printing a cover and printing an interior, usually it is a much more involved print.
Anything a press could do for a cover, they probably could
do for the interior of the book as well. But the difference is, since the cover is only one sheet, and it usually needs to be eye-catching, you’re typically choosing flashier options for your cover than for your interior.
The cover is probably going to use different paper stock, different coating, it’ll have additional coating applied after
printing (lamination), and most importantly for prepress, there’ll be special effects
. These are things like selective coatings, foils, and embossing, and you will need to prepare special masks that tell the printer where
to apply the effects. Available effects vary by printer, but you’ve probably seen most of them at least once on the covers of books you already own.
Some of these differences in the cover process just come down to durability. Thicker paper stock helps the cover last longer, and lamination helps protect the ink from wear.
But the rest of the differences are about appearance. A basic matte laminate has big dull highlights, like this:
A matte laminate cover is held to the light. Note that the reflectance is highly diffuse and produces a large, gradual highlight.
A glossy laminate has much tighter highlights, like this:
A glossy cover. Note the individual bright highlights, and lack of reflectance elsewhere.
But in both cases, the cover responds uniformly. For a more eye-catching cover, multiple
types of lamination can be used with a mask to vary
the lighting response over the cover, like this:
A soft-touch laminate cover with "spot UV" (or "spot gloss") applied on the title. Note the lack of reflectance everywhere but the title, which is highly reflective.
And that’s just the beginning. You can add foils, you can add embossing, you can add flaps — I’m sure if you can think of it, it’s been done by a press somewhere
, for some
publisher, who was trying to come up with something unique to catch a reader’s eye.
As with everything else, the only way to really
know what you want here is to look at samples and see what matches the theme of your cover best. But in the meantime, if you’d like to see how light reacts to the three cover examples above, you can also check out the video I posted on our Spot UV backer update
Once you’ve picked all your stock and process options, it’s time to think about layout and binding.
Once your files are deemed ready, the printer will use a special computerized system to take batches of your source pages — usually called “sides” at this point — and lay them out in a grid the size of the paper stock. Each grid of images will then be mechanically transfered onto “plates”, one each for the cyan, magenta, yellow, and black inks. These plates are indirectly deposit the exact right pattern of ink across each page as quickly as possible as the paper moves through the press.
This is one of the most expensive parts of the printing process, since the plates are real, physical objects that have to be created. As a concrete example, if your graphic novel is 192 pages (like ours), and 8 pages (“sides”) of your page size fit on one side of one sheet of paper stock, then that means there will be 192 pages divided by 8 pages per sheet-side times 4 inks, or 96 physical plates!
As we’ll see in Part 3, print jobs are best thought of as a high fixed cost plus a small per-book cost, and this is why: creating the plates and loading them into the press for each sheet layout costs the same amount of time and money whether you print five hundred books or five thousand. So the more books you can print at once, the cheaper each book becomes.
Once paper is run through the press and inked on both sides, the resulting sheets obviously can’t be bound directly: they are much larger, and contain several different pages of the book. So before binding, sheets go through some combination of cutting and folding to produce bindable sections called signatures
. These are then stacked into units called book blocks
for binding. Each book block is an entire interior of the book, in order.
Much like inking, the folding and cutting cannot be perfectly
precise. It’s a mechanical process, and there will be some small variation in exactly where a page is folded or cut from the larger sheet. So your pages cannot
be laid out on the sheet perfectly abutting. There must be at least some space between the edges of any two adjacent pages on the sheet, otherwise small variations in the cut position or ink spreading would cause artifacts along the edges of pages as the neighboring page’s ink encroached.
It’s for this reason that source pages for print should optimally contain a padding region around the page that is meant to be thrown away.
This is typically called bleed
. Including the bleed in the source material is not particularly important in many types of books, because the pages are typeset against a blank background. But in a graphic novel, where images can extend all the way to the edges, it can be critically important. Including a bleed region and extending background elements into that region avoids any artifacts that would be introduced when the pages are folded and trimmed. This region is typically one eighth of an inch around the entire page, which is probably more than is necessary on a modern press, but the printer can always choose to lay out only the fraction of the bleed region that they need.
Once folding and cutting has produced all the signatures necessary for an entire book, it’s time to assemble them into book blocks. Building the book blocks is not without its own restrictions, because high-volume presses deal with fixed steps that cannot be trivially adapted to arbitrary page multiples.
At a minumum, most automated presses require a multiple of four
pages — a 64 page book would be fine, but a 66 page book would not be. But depending on the page size, type of binding, and layout, there may be much larger granularity. For example, in the print process we are using for Meow the Infinite
, page counts divisible by 16 are the most cost effective. As with most things, this is information you want to get from your printer before you finish typesetting your book.
Close-up of a perfect binding. Note the solidified glue filling all available space between the book block and the cover.
Once the book blocks are ready, they are bound together. In the case of a graphic novel, this usually means using something called a perfect binding
. This type of binding involves grinding the binding edge of the book block to create a rough, grooved surface. Glue is then applied to the binding edge, adhering the pages together along the edge and “fusing” the book block together. Once the book block is perfect bound, the cover is wrapped around the book block and glued along the binding edge.
Because the cover wraps continuously around the finished book block, it has special dimensions unlike the interior pages.
The cover must be designed using dimensions that come directly from your printer. Based on the page count of the book and the paper stock you’ve selected, they will compute the height of the spine of the resulting book block. You will then have to design the cover such that the back, spine, and front of the book form one continuous image that can “wrap around” the book when printed.
Close-up of a hardcover binding. Since the binding was not flooded with glue, the signatures are more clearly visible.
So, much like knowing the proper page multiple, knowing the proper spine height is something you can only
do correctly with information from your printer.
Well, it’s hardly everything. It’s just everything I’ve learned so far. There’s surely a ton of stuff I don’t know, and probably some stuff I’ve gotten wrong. My hope is that at some point, if the world manages to return to something like normal after the pandemic, I can visit the press that’s printing Meow the Infinite
myself and see how everything works in person.
I will leave you with one final piece of advice. Even if you forget about everything else in this article, remember to do at least one thing
before you work with a printer on your own graphic novel project: scrutinize their samples
. Tell the printer you’d like to take a look at their work, and that you’re printing a graphic novel. They should be able to send you a sample of one that they have printed so you can look at it and see the quality of their work.
Look very closely
at every aspect of the printing. Look at pages from different parts of the book. Look at the binding — it should look flawless, and not have any glue or ink issues.
When inspecting the binding, you shouldn't see anything like this! Glue and ink errors along the seam should never become visible unless you physically force the pages to separate.
Look at the ink registration. If you can see visible differences in alignment of the cyan, magenta, yellow, or black inks, that’s a very bad sign.
Example of bad ink registration. The magenta and yellow passes were very poorly aligned on the left, and the cyan pass was poorly aligned on the right.
If the print shop is diligent about aligning the ink passes, it should be difficult or impossible to see any
variation in placement of the ink pases with the naked eye.
A professional print shop should have registration like this. Note there are no visible offsets on any of the ink passes, and you see the chromatic abberration of the camera taking the picture before you see any in the actual print work!
And of course, get a sense for the overall quality of the materials, finish, and feel of the sample. Nothing should feel “off”. Any good press should be able to produce a bound volume that looks and feels great!
Well, I know it was long, but I hope you found the intricacies of printing as fascinating as I did! Modern presses are really pretty amazing, and if you’re looking for something interesting to do, I highly recommend spending some time watching “offset printing” videos on YouTube! Especially crazy are “web” offset printers, which are way higher volume than cut-sheet ones.
That’s it for part two. Coming up next in part three
, Anna will be walking us through her drawing process for the comic. Until then, thanks for reading, and another big “thank you” to all our Kickstarter backers!