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A real illusion - the glare effect
& Comic Book Picture 5, The Island
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The light from the lighthouse in Comic Book 5 appears a bit brighter than the other white areas in the image. That's an example of the glare effect, rather more vividly demonstrated to the left. (There's also a stronger version of the effect in comic book picture 15, The Caterpiller). This astonishing effect seems only recently to have been published. It's a real illusion, unlike the other picture effects here, which create illusory realities. The apparent glare is evoked for us by the gradation from black to white in the rectangles enclosing the central square. It's only been written up so far, as far as I know, in recent, seriously technical scientific papers, such as Daniele Zavagno and Giovanni Caputo, The glare effect and the perception of luminosity, Perception 2001, (30) pp 209-222. If that's for you, you can read a synopsis (or the whole article if your library subscribes) at www.perceptionweb.com/perabs/p30/p3009.html.

But not to worry if you haven't yet quite got round to getting a PhD in perception, all you need is a graphics package that includes a gradation tool (I use Adobe Photoshop), and you can experiment for yourself. It's magic. There are other effects to explore. Try, for example, drawing a demonstration like the one to the left, but in a tonal scheme from black just to pale grey, instead of black to white. You will find that you can create the weird effect of a grey glow. What happens with different colours?