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So i took my senior pictures and it said it was at 72 dpi. My school said they needed pictures to at least 300 dpi. I researched and found out that 300 dpi is the best printing quality. I changed the dpi from 72 to 300 but i did not resample the image so the length and width of the picture remained the same. Is this something good or bad? I'm scared that I did something wrong and that my picture will be blurry in the yearbook. Help please!