If you are looking at buying a projector, don't get too caught up in all the specifications. The problem is that there is no standard for how manufacturers rate the brightness, contrast or other specifications of their projectors. Each manufacture rate their brightness (lumens) differently from varying distances under varying ambient lighting.
However, you can use lumens and contrast ratings to compare projectors made by the same manufacture. It makes it easier to determine the differences between models within the same price range.
The best thing you can do is try the projectors under the conditions that you intend to use it. If you want to show only movies at dark on a 10 ft wide screen, you can get a decent projector for under $500 – really.
