Basic Rendering Techniques

Product Design Sketching

Basic Attributes of Colour

A colour can be denoted by its HSB value, i.e. the 3 attributes:

Hue (its location in a colour spectrum) Saturation (the intensity of colour pigment) Brightness (the intensity of light)

Saturation vs. Brightness

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HSB Values

You may use the colour picker of Adobe PhotoShop to identify the HSB values of your colour pencil

Adjust hue and saturation

Adjust brightness

Creating Different Tones Using Dry Media

Three ways to create tones:

1. By intensity of pigment / strokes

2. By using different degrees of colour saturation

3. By using colours of different colour temperatures (hues)

Varying Intensities

Greater stroke pressure represents shade

Medium pressure represents mid-tone

Lowest pressure represent highlight

Best for light colours

Varying Saturations

Reduce the saturation either by choosing a colour of a

lower saturation value; or

Using grey / black colour as a blending agent

Best for natural colours

Varying Colour Temperatures

Use a warmer hue (e.g. orange) than the midtone colour for highlights

Use a cooler hue (e.g. blue or purple) for shades

Best for vivid colours

Colour of an Object

The color of an object being seen is determined by: Local colour (of the object’s surface material) Ambient colour (of the light source) Reflected colour (from another object’s nearby)

Light and Shades

Identify different light zones and then create tonal values:

1. Highlight 2. Middle tone3. Shade 4. Backlight (for curved surface)

Shades and Shadows

Shade is the surface or area of a surface not facing the light source

Shadow is the area of a surface blocked by other objects or by other parts of the same object

Casting Shadows

1. Use projection lines to simulate the light rays

2. Matching key points along the object’s contours on the surface on which the object is placed

3. Define the edge of the shadows 4. Render with a cooler colour

Shading the Cube

Product Design Sketching Activity