Originally Posted by
William W
My initial thoughts wander off as to firstly whether or not your brother has settled on a 90~105mm FL Macro lens - or are other FL in the offing?
However - that stated: between the two lenses mentioned, I have the EF 100 F/2.8 Macro and I have second hand experience with the Tamron (the new model that you cited). My view is that both are excellent:
> the Canon is a tad sharper wide open but if your using at F/4 or smaller there's little difference.
> (I believe) the Tamron will NATIVELY mate with Tamron Extenders, on the other hand you'll need to plonk and extension tube between the Canon and the camera.
> the Canon has an excellent Tripod Mount and it sits in a really handy position, not sure what arrangements you'd need for the Tamron.
> the Tamron has VC, my experience is that's excellent for using the lens a a typical Prime Lens, but for Macro (1:1) and reasonably close "Close Up" it gains about the equivalent of 1 Stop, to my mind that can be countered by 1 Stop more ISO and a modern camera will eat that.
> pedantically if the Tamron stuffs up on a Canon Camera, then Canon won't want to know you - if the EF100/2.8 stuffs up then you have much more traction (though you might have to be aggressive), though lens/camera stuff ups are rare, they're more common, or seem more common, with third party lenses.
My bottom line is that if the lens is being bought for an equitable dual purpose, then the Tamron, because of the VC, is a better choice, on the other hand if it is being bought for mainly Macro and Close-up use, then the less expensive, value for money Canon is a much better purchase, that is stated with a bias that I don't need the little assistance that VC (or IS) provides for Macro shots.
I have no experience with the Sigma mentioned.
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If your brother is not decided on that FL, (and I mean decided as a result of specifically thinking through and selecting that 90~ 105mm is what he requires), then the question as to what to buy is much, much broader and that requires more information on his present Kit and his intended uses for the new lens.
WW