[Guest]

My guess is reaching the limitation of resolution of the lens. I.e, newer aps-c like the 7d have smaller pixels and therefore require higher resolution from the lens to maximize the sensor. Having said that I did not actually check how it 'fared' worse and presumed (perhaps incorrectly) it was a resolution issue.



[quote name='Rover' timestamp='1325692993' post='14288']

This lens is very high on my "wanted" list. A bit odd that it seemed to fare worse in the APS-C tests than FF ones (?).

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