MKII wrote in post #12724102
i am in search of a new lens...i am between the 100 macro and the 70-300 is usm. The use of the lenses will not be much but i want one just in case...the idea of a telephoto lens doesnt sound as intresting as a macro lens.. so i i would like to know some thoughts for the macro lenses from your experience..
expect for the 100 L cause iwont give so many many for a macro lens..
thanks in advance..!!
ps. i will use it with my 7d..
Hello there 
Canon makes 6 macro lenses, and I have personally owned and used 4 of them: the EF 100mm f/2.8 non-L, the EF 100mm f/2.8L, the MP-E 65mm, and the EF 180mm f/3.5L. As a matter of fact, I have written a blog post
on the subject of my experience with Canon macro lenses that may be of some help to you.
Regarding your statement of "giving up" money, how much money you give up is not always a waste ... it can, in every sense of the word, be an investment. I don't know how serious you are about getting into macro photography, but if you get hooked (as I have!) you will want to do it all the time ... and with macro you can 
If you are planning on photographing live subjects, in my view you need a 100mm lens, at minimum, not to be forever frustrating yourself "scaring away" your subjects. I personally hardly use my 100mmL anymore, in favor of using the 180mmL, precisely because the 180mm gives me twice the working distance of the 100mm, so I am not always scaring away butterflies and such. This allows me the use of a tripod, which to me is critical for macro work.
If you don't use a tripod, then the 100mmL will serve you FAR better than will the elder "non-L" macro lens, because that image stabilization allows you to "keep" far more shots than without, and I can say this definitively as I have shot thousands of macro shots with both the non-L and the L 100mm lenses.
If you do use a tripod, then the non-L will do you just fine, as will the very inexpensive Tamron 90mm, which is about the best buy in non-IS macro lenses when used on a tripod. Just remember, the best glass and sharpest "potential" in any lens is utterly wasted if you move and have a blurry capture ... so if you're not using a tripod, and you don't have IS, you will lose far more shots than you would with the 100mmL.
I actually did another blog post comparison
of the Tamron 90mm to the Canon 100mmL, as a response to another discussion of "cheapness" versus features ... and what the hidden costs can sometimes be that you don't really think about ... especially with a macro lens that "reaches out" to bugs (like the Tamron) versus a lens with internal focusing elements that allow it to stay true ...
Cheers & good luck!
Jack
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