Although this would seem to argue.
Now i am lost F8 looks alot clearer????
Thats what I mean, the numbers on the first site would say that f5.6 is better but looking on the second link, the examples show the opersite
if im reading that right it should mean that this is correct :-
50mm @ f/5.6
200mm @ f/5.6
300mm @ f/8
This would give the sharpest images.