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I'm not sure if my image quality is OK. How can I tell?
One of the first things the reviewing staff will check is the curving lines in your image. If these are pixelated, then they are lower quality. Another easy way to tell is to look at the "noise" in the JPEG file. If the JPEGs are too small or low quality, there will be a lot of pixellation and general blurriness to the image. Please make sure you are viewing your image at 100% resolution when checking the quality.