Monochrome Manipulation Recap

• The Sabattier effect is simply maintaining shadows whilst inverting highlights to form a mixed positive/negative image.
• Images with smooth reflecting surfaces are usually suitable, but so are many other images.
• The effect is controlled by fine positioning of the transition points
• The amount of the effect is controlled by the positions of the control arrows on the output side of the histogram.
• Assess the tones in the image to identify tonal ranges and likely transition points before manipulating the image
• Transition points generally lie in smooth areas of the image that have a tonal gradient
• It’s possible to invert more than one tonal range. Generally 2 or 3 inversions will produce striking and pleasing results.
• Multiple inversions interact with each other.
• Build up complex inversions in stages after considering the image as a whole first.
• Adding and adjusting anchor points will control the inversions and stretches.
• Interesting effects can be subtle – or striking.
• Natural tonal changes can be enhanced, reversed or manipulated for effect (sky example).
• Achieving these effects in PWP is simple and easily controllable.
• Posterisation is likely and can enhance or degrade the image. Use 16bits/channel to minimise the effects. Generally, like film grain, it’s acceptable and enhances images of this type.
• Many different results are possible from a single image.
• Solarisation (for our purposes) is a narrow, strong application of the Sabattier effect.
• All the techniques discussed here will be used in the colour transformations discussed later.
• Experiment (and have fun)!