Im looking at a good photo on my computer (Canon SX170 ) , I take in high pixel and load them to be 800 which is aprox 8-10 inches big so why do they go all grainy when I load to ebay , its like they are trying to make them clearer by brightning them and using a sharpening filter and its causing perfectly good photo to go grainy because they were already sharp . should I make them smaller and blurry to get a good result
