Macro is 1:1 or greater....no ifs butts or maybes about it in my eyes. I don't count crop factors as additional magnification and it is common to see magnification alongside format to give scale. Always has been AFAIK. That said I use APS-C instead of a bigger format as I do appreciate that the smaller format makes life easier as higher magnifications are more difficult. (I've used the MP-E on APS-C, APS-H, FF and 35mm)

210mm? Can't say I noticed a problem finding my targets with a 180mm macro lens on a 40D. (I think the MP-E works out as 600mm+ equiv focal length on APS-C when set for 5:1.....depends what you are used to I guess. Haven't a clue how I've got useable hand-held shots from it at 1/6th of a second...luck I expect

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