I shoot a fair amount of macro - mostly flowers - and currently have a 100 f2.8 (non-L). It is relatively lightweight and I can carry it all day as long has I don't have the 580EX mounted on the camera as well. IQ is excellent.
A friend is offering me his 180mm macro for a good price - about the same as 100L. The 180mm f3.5 lens is reputedly THE last word in Canon macro lenses in terms of IQ and working distance. It is the solution professionals use. I am not a professional, however I wouldn't mind extra working distance and creamier bokeh. The tradeoffs are weight, cost and aperature. The lens is probably too heavy to carry on a hike.
The 100L reputedly offers largely the same IQ as the 100 non-L but adds some flexibility for non-macro work by virtue of the IS (as well as weather-sealing which doesn't interest me). The lens is larger than the non-L but nowhere near as big or heavy as the 180mm. I reckon there are plenty of better lenses for low-light portrait work (50, 85, 135).
So, I'm mulling over the 180mm purchase and comparing it to the 100L since cost would be similar. I can't see why I would go for the 100L other than weight/size.
Your thoughts?


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