http://www.456bereastreet.com/archiv...s_readability/
"I know I am not the only person to find it very uncomfortable to read text on sites with inverted, high contrast designs.
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I also find that high contrasts between different areas of the page cause problems. An example is when the main content area uses dark-on-light and there is an inverted sidebar right next to it. It hurts my eyes, and if possible I make my browser window narrow enough to hide the inverted part of the page when I visit sites that have that kind of design.
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You should also consider what Mark Boulton has to say in Five simple steps to better typography:
When reversing colour out, eg white text on black, make sure you increase the leading, tracking and decrease your font-weight. This applies to all widths of Measure. White text on a black background is a higher contrast to the opposite, so the letterforms need to be wider apart, lighter in weight and have more space between the lines.
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