Case in point is the "Godfather"-inspired art for "Jeff Catches A Cold II" (Click This Link).
Recently, I got an e-mailed query: how did this image come together? I superimposed sketchbook art onto a rendered background. How did the background art get rendered?
First, I used an image from "The Godfather" (copyright Paramount Pictures, 1972) as a reference. I digitally sampled a palette of colours from the scene using Photoshop. I also used the scene to block out the basic shape and perspective of the building, road, and car, which saved a lot of time and effort.
Then, I imported the image into my ancient copy of Corel Painter. Photoshop is great for working on photographic media, but even an old copy of Painter blows away Photoshop when it comes to simulating brush strokes. I also use an electronic stylus, which is kind of like a mouse shaped into a pen that can be used like a brush - and never any spilled ink.
Above is one of the intermediate steps. The flat colours represent areas that I have blocked out with samples from the original still picture. The areas that look "painted" are parts that I have gone over with the stylus. The pink in the distance is supposed to represent my infected throat. I was going to put more gooey cellular detail in that, but my cold really is slowing me down.
Here is the finished background, before I inserted the characters. I've painted over the flat colours. I can use colour-based selections to precisely define which block of colour I want to add brush strokes to.
The next step was to colour-correct the image. Ordinarily, I would not do this, because I used sampled colours. However, screenshots can be dark. A simple adjustment of the gamma curve in Photoshop both brightens the image and adds a little contrast. The Curve is the fastest, most reliable way to make this change, but you can also use the brightness and contrast sliders. As it happens, boosting the curve also brings out brush strokes and washes out the colours, giving the image the appearance of watercolour or gouache. That's the kind of look we are getting used to seeing from Japanese/Eastern animation.
An interesting art exercise if you have Photoshop or any art program where you can adjust brightness and contrast... first find a decent picture of an oil panting. Something dark and baroque would be perfect. Try Vermeer. Load the image into your program. Boost the brightness quite a bit and contrast half as much, and you will transform the oil painting into a "watercolour". In Photoshop, choose CTRL-M (Image/Adjust/Curves), and click and drag a single point in the middle of the line upwards and to the left.
Photoshop makes a great tool for analyzing artwork. You can use it to invert pieces, drain them of colour, separate the colours into components, or adjust the gamma levels to see exactly how the artist used paint to make illusion and reality on canvas.