In the past 4-5 years visual effects stopped being something extraordinary and became a part of almost any production regardless of the scale. Would it be a 100 million dollar Hollywood feature, TV series or an independent film project, ability to enhance visuals with computer generated imagery (CGI) have become accessible to almost everyone. In today's world of money and profit, producer thinks of a cheaper way to achieve something that used to cost millions. Visual effects come in place when the world we live in cannot provide us with imagery we need or the cost of recreating certain phenomena would jump over budget.
One of the most important parts in visual effects, and also one of the easiest and cheaper one to do is a matte painting. Regardless of whether it is painted on a piece of glass or generated on computer it serves one purpose - creating or extending the virtual space of the scene. As every art, this one has its secrets and cheats. Unlike traditional art, where "cheating" is considered to be a bad manner, matte painting requires final product to be done in the most efficient way possible. Don't be afraid to make shortcuts if they are possible, because time always works against you.
In this tutorial I will cover a process of enhancing footage to fulfill the needs of story. It all begins with the script that calls for some change in original footage. After agreeing that the best way to specific shot is to enhance it digitally, I start to create a concept of how to incorporate these enhancements in original footage. There are many small details that have to be overlooked for the purpose of a smooth compositing. First I have to think of a camera movements and composition. In my case, the idea to create a matte painting came before we started filming, so I didn't face any problems related with an unexpected change of plans during production.
The story called for a remote location covered with snow for all outside scenes. As the film has mainly interior shots, we decided not to go to Colorado, but shoot background plates here in California and just paint the snow in. The example I use here is a test that was done to prove that it would be financially better to make a painting. We shot a background plate using still camera then replicated lighting conditions on a green screen stage in Ventura, California for our foreground plates, which had actors and a car in it. We decided not to have any camera movements to speed up production, because outside shots weren't important on the bigger scale and had to be simple.
I started with a picture I took in Santa Barbara, a very nice and warm city, where snow is something that people don't see very often.
First I had to clean the picture by eliminating all of the unnecessary objects and paint parts of the plate that were obscured by the removed parts of the picture. This process requires a vision of the final product. Without understanding what the final image is going to be it is very hard to make decisions on what has to be left. The main rule I learned while doing matte paintings is that if you can leave specific parts of the picture intact or use a photo to replace it - then do so.
Nothing will look as realistic as a real life source. For the final touch up, I darkened the color of the road to add wetness to it.
As an empty background color I always use the dominant color for specific painting. In this case it is the color of the snow - white. The purpose of this is to being able to visualize your final product in the early stages. In this case it is also the color of the sky, so I add a little gradient by darkening the horizon line.
Speaking of a horizon line, it is good to make one early on, so you won't have and unexpected perspective artifacts. This is done finding existing perspective lines (blue) and drawing the line through the point of their intersection (red) which will be our horizon. After we have established all necessary elements it is time to start painting. The next step would be to create a ground plane. I painted some free strokes using mainly three shades of snow from light to dark gray. The idea behind the matte painting is the same as behind impressionistic painting. You just create an impression, but on close-ups the reality breaks on strokes and colors.
As in real world, there can't be any flat colors. Of course there are exceptions, but the nature is full of texture that mixes colors in a very organic way. I said before that if you can use photos the use them. I applied a black and white photo of a grass field on top of the ground plane to create imperfection in color. To do so, I placed a layer of grass on top of ground layer in photoshop and overlayed top layer over the bottom one. This creates a more dynamic range of shades as well as adds a texture to the ground plane.
Next step is actually painting snow on our plane. Before doing any matte painting it is always good to do research on a subject of your painting. In this case it is snow. Snow might seam a very easy subject, but in fact it has a very interesting nature. Under different weather conditions, snow has different color, shape and interaction with environment. In my case it hasn't snowed for couple days, as well as it is not windy, so the snow is not blowed off the house.
If you look closer you can see the simplicity of technique I used. I projected the snow on every surface as if it was falling down directly from the sky. I added little imperfections, but the underlying idea is very simple.
With a little help of imaginations you can predict which areas would be exposed to the snow in case if the snow was falling in the straight vertical direction. The ground in front of the house has a little different technique then the snow on the roof. Again, the method I use for specific areas of this painting is used on research I do. I can't stress enough how important to the your "homework". In the case of the snow in front of the house, I chose areas that would be physically blended with the underlying ground plane. I assumed that outside temperature is very close to 0 Celsius. Hence, the areas where the snow is not thick are more "wet" and thus blended with the ground.
I used this blending technique on the areas where snow meets ground areas and sometimes on the snow itself to create uneven texture. Besides snow I added small vegetation, like frozen grass and small bushes. This added more realism to the flat areas of snow. Another reason for this was to create an atmosphere for this painting. I think that trees and the way they branch can greatly affect the mood of the scene.
On this picture you can see a relatively simple tree behind the house. This is the first step in changing direction for this painting.
As with snow, I used plain color, after I finished the tree structure, I moved to adding snow with the same technique I used for the house roof. Since we have a foggy atmosphere, this tree has to be a little lighter. If I had a plain background with no intention of having something behind this tree I would change the opacity. Rather then doing it I went to Image->Adjustments->Levels to reduce output black level. If the background was something other then gray color, I also had to tweak its color palette.
Next I would fill out the background plane. I usually create 2-3 trees that I'd scale flip to randomize it a bit. Depending on the type of a matte painting you have to put different amount of dedication. If the painting will be slightly out of focus, or the camera will have some movement, I don't spend much time on background objects, or on something that doesn't have viewer's attention. As with the previous tree I changed output black level to match the fog depth.
Then I paint the rest of the forest, recycling the trees I used before plus using some photos. I painted some snow on the fir trees and then put several of those on the background. Final ouch is to make some foreground trees. It's good if you can get some photos. I finished them by painting snow and adjusting levels. For these fir trees I didn't worry much that they looked duplicated, as I painted snow on individual trees differently.
Now, when the painting is done, you can change it to whatever the shot requires you to use it with.
By using simple color correction techniques, I was being able to change the time of day or the mood of this particular painting. Here is what I ended up using for production purposes.