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Message: <blockquote data-quote="Vespobuteo" data-source="post: 3336756" data-attributes="member: 120830">* generally you could say that closer to 100% is better* the blue lines indicate "sharpness" (lower cycle pattern, 20 line pairs/mm)* the green lines indicates "contrast" (higher cycle patterns 40 line pairs/mm)* the dotted line should follow/be as close as possible to the non-dotted line of the same color.* left in the diagram (0) is the image center, so there always be a sharpness/contrast fall-off towards the edge.Curves shows measured or theoretical values at full stop. Most likely theoretical. But it still gives a hint on the level of performance.The above indicates that, fully open, the lens is sharper at 400 mm than at 100 mm. But stopped down at 100mm it will be sharper naturally.Most manufacturers seem to have charts for 10 and 30 cycles so this chart will not becomparable with for example Nikon or Canon. Less pixel density for FF and DX cams probably make it more relevant to use smaller cycle values.</blockquote>