Spectrum said:
I have both AF & MF body, so as I can see that either the Sigma 105mm & Tamron 90mm is within my choice & budget, which of this lens performs best?
I have chosen Sigma 105mm over Tamron 90mm
I havent tried using Tamron 90mm, so, I cant speak anything about it based on personal experience.
To me, sharpness is not an issue when it comes to these 2 lenses.. all macro lenses are made to be sharp. Sigma rated 4.1 vs. Tamron is rated 4.2 @
www.photodo.com. The difference is negligible I must say. Infact I always use 1.4X with my sigma and still produce a very sharp and pleasing result.
I've seen Tamron built, and I can say that I like the way Sigma 105mm was built.. it's EX finished after all.
Why did I choose Sigma over Tamron?
Because of the 15mm difference. That's all.
1) The longer the focal length, the lesser the background coverage. Hence, the selection of background for macro work will be more flexible as you are covering lesser portion of the background. Yes, It leads to a better bokeh.
2) The working distance to achieve certain magnification is farther compare to Tamron (negligible perhaps).
These are the 2 main reasons why the 50mm range is not advisable for macro work, esp that of insect macro. And that's the same reason why I always put 1.4X with my Sigma 105mm macro.
Hope you could find the right lens for you.