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I've recently seen the news about Canon's 5ds and 5dsr with their 50mp res sensors. Now I've read on some other forums that you would need some L lenses developed recently ( 5 years) or those woth mark ii versions to be able to fully resolve the full resolution.
My question is: does lens resolution really matter when it comes to real world results? (by 'real world results' I don't mean pixel peeping, but rather viewing photos at reasonable sizes maximum, like 30" enlargements) If lenses can resolve film with details, what makes it different in such a way that they cannot resolve sensors?
I've some L lenses myself, canon 135mm f2 and 35mm f1.4 but these were made in the 90s and they never had a -ii version replace them.