My non-TUAW job is in print journalism, where I spend my nights as a designer for a newspaper in central Pennsylvania. Part of that work involves being able to estimate, from the glance at a photo in InDesign or a paper dummy, how much of a story I can fit on a page, photo dimensions and more.
The same goes for online design. Design veterans will tell you that knowing how big your elements are, aligning them, how they'll look on various screen sizes and other metrics isn't exactly easy. Icon Factory and ARTIS Software's xScope is a premium tool for helping streamline design for the web and the screen.
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