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I own a 10.2MP Sony A230, and I like to take it with me to important family and friends events...
I rarely print my photos, and even then never more than around A4 size, they generally end up on facebook or zipped up and sent to whomever asks to see them. I was wondering whether it would be worth it to downscale these 10MP images, for the sake of image quality, to something around 6MP... and, if so, should I simply set my DSLR to take photos at a lower resolution or take them at 10MP and then downscale afterwards using some PC software?
Also, given the effects oversampling can have on noise (or, at least the effects I have been led to understand it has) would this allow me to get better quality images in low light using higher ISOs?