I enjoyed creating my short post the other day about the “in-process” cover art for my latest book, so I decided to break down how I layer my cover art and how I proceed from line art all the way to finished, filtered images. Plus, it gives me a nice break from writing.
First, the tools I use are pretty much 1) pencil and paper (and pen), 2) A scanner, and 3) GIMP (open source photo editing tool). I’ve been using GIMP for aeons now and have some pretty comfortable rituals to build up images layer by layer.
First: The Line Art
When I’m working on a book, I usually will sketch up 2 or 3 ideas that correspond with something “key” in the book. In the case of this image, from “The Halls of the Shadow King: Into Deeper Waters”, there is significant sea travel from Rome down the eastern coast of Africa. Lots of time in the water. So I came up with some drafts that showed my main character (a little older than he was in the first book) with people from a supporting village in the Kingdom of Aksum (present day Ethiopia). Once I have a sketch I like, I ink it in with fine tip sharpie then scan it into the computer. An important step comes next as I open it in GIMP (usually inside a book cover template where I paste it as a layer). I select the line art layer, go to the “Layer” pull-down, then “Transparency”, then “Color to Alpha”. What I’m trying to do is remove all of the white and leave just the black line art. That way, layers below the line art show up through–but not over–it. Then I play with darkening, thickening, etc., the line art to get it the way I like. At that point, it looks like this (shown with a plain white background behind the line art so you can see it).
Note that I like to leave some of the pencil in as greyscale, whereas the darker lines are penned in by the sharpie. I also tend to leave something like the squiggles for the ocean waves in pencil. Eventually I’ll fill these in with GIMP, sometimes using brushes that specialize in waves. Often I erase the line art in a place like the background if I feel like it is distracting, but I almost always leave it for the foreground characters, the ship in this case, etc.
Next: Background Layer
Generally, the next thing I do is start modifying a basic white background layer with whatever will be in the back. I make the line art visible and paint on the background layer “through” the line art. In this case, I chose the ocean and the sail as my main background elements. I painted the whole ocean at once for the sake of coherence/continuity of the waves, knowing that the ship layer and the character layers (and the line art) would sit on top of it. Here’s what the first pass at the background looked like.
As mentioned, I like to use GIMP “foam” brushes that make the foam on top of the waves look good. These brushes are created and open sourced by people all over the web and can be downloaded to your GIMP application. This same approach works for Photoshop too, but since GIMP is free, I’ve always used it. There are cloud GIMP brushes too, but my memory is that I hand drew these in GIMP using my Wacom Tablet and standard GIMP brushes.
Next: Color Layers
The next thing I typically do is build multiple layers to cover other elements in the image. I have always called these generically “color layers”. I’ll have one color layer for the boat, one for the characters, one for things like birds maybe, etc. These all start as a new “transparent” layer so the layers below show through. Keep in mind that the top layers (the ones you see over everything else) need to be on the top of your layer stack in GIMP (and background is typically the bottom. Here’s an example of an early “Character Color Layer”.
On these layers, I tend to be very sparing with colors and I pick 4-5 colors from one color palate. I find this keeps the drawing from being overwhelming. If I do a bad job here, I can always “cartoonize” the final flattened drawing down to 8 colors or some such.
Finally: Flattened Layer for final edits and Artistic Filters
At some point, I decide which of my 20+ layers are keepers and will become part of the final image. I will show only these layers and build a single flattened image (note: I never have Text in my flattened image. That comes later on other layers). This may or may not be a good approach, but I’ve used it for years, with the notion that I’m just doing light touchup on this flattened image. If I mess stuff up, I just hit undo. This layer is very good for fixing color issues (darkening/lightening/exposure/hue/brightness-contrast, etc.). I also use it to do a lot of “sunlight effects”, which are typically really light, low opacity effects trying to accurately capture the lighting of the scene. Once I have the lighting and colors appropriate and I’ve fixed anything about the original layers that is annoying me, I’ll apply various artistic GIMP filters. To be honest, this often helps fix problems with the image that I might not be good enough to fix. One artistic layer that I chose early on for all the books in The Halls of the Shadow King series was “canvas”, which imposes the structure of a canvas on the image and makes it look like a highly-detailed oil painting. See how the flattened/filtered image looks below.
Closing – The Rest of the Book Cover Process
This front cover image becomes the main feature of the whole book cover, but you’re not done yet. I have a template for a 9×6 trade paperback cover that contains the front/back/spine. I then use GIMP to fill in Text on top of everything. Here’s what this looks like for the final book cover copy.
One thing I’ll note too is that this process allows you to do a rev 2 on your cover art if you decide after a year that things need to be refreshed. I did that with book 1 of this series, where I felt after a while that I hated what I did with my main character’s hands (hands are hard for me to draw… lots of sketching and erasing) and thought the art should be lightened. All I had to do was then go in and edit individual layers (line art, character color, background) and make changes, flatten the changes and re-apply filters. Piece of cake!