All other aspects being equal, big lens gather more light. But this is a big problem in the 100 buck price range your other posts hint at.
if two camcorders have the same CMOS sensor specs (size, shutter speed, resolution, etc)but one has a larger lens because it has more zoom capabilities than the other smaller lensed one, will the larger lens one take brighter vid/pic than the smaller lens just because more light is let through the lens?

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