NEIL BOTTRILL
PHOTOSHOP RENDERING

Neil Bottrill, a Coventry University graduate has put together this tutorial to show his techniques for using Photoshop in order to achieve very realistic side view renderings. If you are interested in seeing more of neil´s work you find further examples in his CarDesignNews portfolio on, www.cardesignnews.com

Make sure the selected sketch is free from major perspective issues; even in a side view there is a value of depth. Use whatever medium you feel comfortable with, I lightly sketch in pencil first, then finalise with a black biro. I find this method provides a clear, precise guide with the extra benefit of the scanner not picking up the hideous mess that is my pencil sketch. Luckily the sketch will not be visible on completion of the render.
Scan the sketch at 300 dpi. The reasons for this being;
1. The image can be printed out on A3 at 200d.p.i. with negligible difference in quality.
2. The largest brush head is 300 pixels so higher resolutions result in a lot of brushwork.

First duplicate the sketch by choosing ‘Duplicate Layer’ in the Layer menu and setting the layer style to ‘Multiply’. This layer should remain above all subsequent layers. Create a new layer and fill the wheel wells with black. On another new layer, import the wheels. Either cut and paste existing wheels or use wheels that you have designed and already rendered in Photoshop. I save all wheel designs in a folder so I have a library of rims to choose from. For a detailed tutorial on wheel rendering see Allan MacDonald’s tutorial on Car Design News.

New Layer. Create a boundary around the bodywork. Creating the boundary can be done in two ways, by using Paths or Polygonal Lasso. Polygonal Lasso is the quicker tool but, as the name suggests it creates polygons, following a curve will result in a series of straight lines. Zoom in and keep the lines as short as possible. Paths are tricky to use at first but they offer complete control over the tangents and radii of the curve required. In this instance a Path is better due to the large nature of the component and it will need to be saved for future use (See inset). Fill the boundary with body colour.

Create a boundary around the wheel arch lips, copy and paste onto a new layer. On the bodywork layer use the Dodge tool to lighten the upper facing areas of the car and the Burn tool to darken the downward facing surfaces. If your design has swage lines that separate upper and lower surfaces (like this car) create a boundary to get a crisp divide between the light and dark.

Create a new layer above the bodywork but below the copied wheel arches. On this layer use the Paintbrush tool to further sculpt the design. Rather than using black and white, use a very light blue for surfaces pointing skywards and a dark brown for surfaces facing towards the ground. Vary the opacity (maximum 50%) of the brushes in accordance to the position of the surface and light source. Once the Paintbrush work is done, Dodge/Burn the lower part of the copied wheel arches until they match the bodywork then merge all bodywork layers. Path/Lasso the light clusters and cut.

On a new layer below the bodywork create a Path/Lasso for the far side glass area. Fill this with a Sky Blue at 40% opacity. New Layer and mark out the far side interior structure (Pillars, Roof lining, Door Capping, etc.) Fill with a mid-tone at 100% opacity and Dodge/Burn for depth (unless the car has a glass roof the light will come from the sides, not the top). Yet another New Layer is needed for the interior components (Seats, Steering Wheel, Fascia) which need filling with a darker tone. Again, Dodge/Burn to apply form. New Layer, mark out the near side pillars/framework and fill with black. New Layer, mark out the near side glass area and fill with a 40% opacity gradient going from sky blue at the top to a slightly darker blue at the bottom.

Select and outline the near side pillars/framework and cut from the near side glass. Inner Bevel the layer containing the far side interior structure (Layer, Layer Style, Bevel and Emboss) and merge with the layer containing the interior components. Apply a small Gaussian Blur and then merge with the far side glass area. Mark out a horizon line on the layer containing the near side glass area, from the centre apply a white 50% opacity Paintbrush above the line and Burn below the line. Inner Bevel the layers containing the glass area and the pillars/framework. Merge all glass/interior layers and use the path from the bodywork to trim to shape, then Inner Bevel.