I couldn't agree more Mason and in fact I make a lot of 800x800 or 1000x1000 renders. I usually zip up my large resolution textures and then use a batch script in Photoshop to reduce them (from 50 to 60% depending) and put in a slight sharpen (Sharpen then fade to about 30-40%). Then you could always zip those adjusted ones up as a lower-res backup and go to the originals if need be.

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