Download all the files needed for this tutorial (select ‘Mechanical Concepts’ from the list)
Regardless of how you get to this step – a simple 3D model, a sketch from a piece of paper, or a crude 3D rough draft from a client – the best thing to start with is a solid line drawing of your tank. From here, we create a new layer set to Multiply blending mode and fill the drawing with solid 50% grey.
While the line drawing may give your tank shape, adding very simple, solid shadows will give your tank its form. These two things will come together in the end to help create a more realistic-looking painting. Drawing a diagram of the light direction, we add shadows, taking care not to make them too complex. Using the Marquee tool (L), we add shadows to the sides by using a Multiply layer to shadow everything that is facing away from the light direction, or under another object.
Early in the process, your painting should read well in light and shadow values. Jumping too quickly into the details will create a noisy, ill-thought-out image. Before this step, be sure that your values are divided into simple light and shadow. Adding colour is the same; applied slowly and carefully. Here, we add a little splash of colour by creating a new layer and very lightly washing in a medium blue-ish grey on the top (reflecting the sky) and a light orange colour on the sides (reflecting earth).
Now that the base colour is established, it’s time to massage it a bit, while staying very simple and only addressing the overall tones of the image. Here we use an Overlay blending mode layer to add a little more vibrancy to the paint job. However, you must be very careful, as Overlay layers tend to push the contrast of an image. If used too heavily your values will become too spread apart, lights will become too light and darks will become saturated.
At this stage in our image we check for mistakes that may have occurred when adding in our base coat. We check, double check and take care to be as safe as possible. But don’t be too hard on yourself, because in the end it’s all trial and error. We feared the tank looked too green, so we applied Hue/Saturation (Cmd/Ctrl+U) and adjusted the sliders until the top of our tank was bluer, as an object lit by the sky would be.
One key element to vehicles, which you will see if you pay close attention to outdoor examples, is that vehicles reflect their environment. The flat panels are essentially a complex structure of mirrors. Once all of our values are reading properly, and we have a nice base coat to work with, we add in the colour of the sky and the ground to use as a map for colouring our vehicle reflections. As before, we’ve kept those colours simple, picking a sky colour and earthy tones.
Photoshop has many methods of streamlining a workflow. One of our favourite tools to do this is the masking tool. By clicking the Layer Mask button, located at the bottom of the Layers panel, we generate a mask that we can then use to uncover our vehicle. Painting on the mask with black hides paint on that layer, while painting with white brings it back. This is faster than erasing, as you needn’t worry about accidentally erasing important information, you simply paint it white again to un-reveal it.
Now that we have a stable base, as well as a background, we can begin unifying the two. Since we know that vehicles will reflect the light above them, we begin bringing some of the paint from the sky into the top surfaces of the vehicle. To make this more convincing, we also add some very simple highlights to the edges of the vehicle that face the light source. We approximate that by picking the sky colour and lightening using the Brightness/Contrast>Brightness slider creates a lighter sky colour.
Convincing elements in a robust tank are the small details located on that tank’s body. Since we have the wire-frame of all of the surfaces of the vehicle, adding panelling should be easy. All we need to do is follow the lines and shapes already laid out for us and create simple square or rectangular shapes within those boundaries. We shade the sides of those shapes according to their relativity to the light direction. This is easier because we have taken care to establish our lights early on.
Another interesting and convincing detail is the method of manual lights. The key part of adding light is that this can help define edges that may be unapparent to the viewer, because of our sky light and shadows. We’ve created a panel within the confines of our wire frame and added a rectangular light by painting first with a dark orange colour. Then we select a brighter yellow colour, create a new layer set to Color Dodge, select a soft round brush and brush in some light.