Hi Didit,
What kind of Macros do you want to shoot? The 180mm Makro from Sigma is well known and a very good lens. You will benefit from the long lens, if you want to take picture sof small animals, which often try to escape just befor the shot, if you use Makros like 50mm etc.
But the Sigma 180mm is an older design. Sigma just introduced 2 new Macro lenses, which you should take into consideration too, depending on what kind of Macro shots you want to take:
Sigma 70/2.8 Macro and
Sigma 150/2.8 Macro
But be aware that no matter what kind of lens of which manufactuerer youa er using, it will give you different resukts, depending on which DSLR you are using it. So the results with the exact same lens might be totally different on a Canon 20D vs. on a Canon 30D
We just created a totally new Sigma section in our Userreview area. I am sure over the time you will find there too some hints in combination with different cameras:
Look here:
Otherwise, someone else had maybe just with your combination experience - or ask the same question also in our Canon sister forum: (
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