That depends on the coin, how much zoom was applied (are you talking about a Morgan or about a fishscale?) the camera and amount of focus, the lighting, and the grading standard that you are using.
For a tiny piece like a three cent silver, I understand the exception. But my point is that a 600x300 pic isn't detailed enough to show the kind of mark that's slight enough for a coin to qualify for a PRF-68+, IMHO
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