Dithering In a dither about error diffusion and ordered diffusion? You're
not alone. Your editor was in a confusion about diffusion as well. But here is what we found out.
Ordered dithering (far right) uses orderly patterns made up of different colors, which when placed over another color, kind of looks like a third
color. This is a throwback from the early days of color monitors when most computers could only display 16 colors at one time. The patterns were always distracting and the colors never seemed very convincing.
Error Diffusion dithering (center) uses a more sophisticated algorithm to create a random dot pattern and as such the image looks a lot
better. The palette option can make a big difference as well. The Browser palette has to select from the limited 216 colors while the Optimized palette looks for the best 16 colors to display the image.
Given the fact that almost everybody has monitors and graphics cards capable of displaying 64 thousand colors to 16.7 million colors, it is your editor's biased opinion the
Browser palette should only be used when exporting solid, Web Safe colors to the Web. Otherwise, the Optimized palette is definitely the way to go.
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