Jan 5, 2006, 16:18
I've hummed and ha-ed whether to give the opinions below, as they are a combination of subjective response, objective testing and just hearsay! I hope that at this point you will add a pinch of salt before the taster.
I bought this lens after reading reviews, comparing mtf charts, line resolution and personal hands on, though the only thing I can truly say is my demonstrable experience is my personal "benchmarking" in relation to my nifty-fifty, the pleasingly sharp Canon 50mm f1.8. The one denominator is that findings of self and others are with a Canon 350D body.
And yes, I know, they are differing focal lengths!
I started my shortlist, as I wanted a sharp prime lens of around the "equivalent "of 150mm on 35mm..or like the 300mm I'm used to with medium-format. The fact that it's macro was only useful to me inasmuch as macros are reportedly inherently sharp lenses.
My list of hopefuls was:
the Tamron
Canon 85mm f1.8
Canon 100mm f2.8 macro
Sigma 105mm f2.8
Basically I lumped together all the mtfs and made up my own little "points" system for centre and edge performance at some key apertures. I really only looked at wide-open, down to f8: chances are, as I'm not using it for much macro work, I don't need to be mission-critical at tiny apertures. Also, I'm guessing that if it's holding up fine by f8, then chances are, as they say.
My Canon 50mm is sharp. Real sharp..nothing less than 1800 or so on the chart, peaking at 2047 at the centre at f5.6. Even at f2.8 we get 1869 and 1805 for centre and edge respectively. Out of all the lenses here, at f2.8 it has the best centre© and edge(E) definition of the bunch, closely followed by the Canon 85mm and the Tamron.
However, notice here that whereas the Canon 85mm at f2.8 has 1866© and 1601(E), the Tamron is already only just behind at centre(1795)..yet already ahead(!) for edge definition, at 1683.
Now, the other canon(100m macro) is ALREADY at f2.8 surpassed by the Tamron for both C and E...1776 and 1670.
At his point it's interesting to note that the Sigma, whereas more free of chromatic aberration than ANY of the others, is the softest of all 4 at f2.8 and f4. The Sigma is no slouch by f5.6, giving C at 1964 and E at 1832.
Yet look at what the company is, bearing in mind that the Sigma's resolution is softening at the edges already(the Sigma's C carries on well through f8 and 11...bear in mind this will be worse on a full-frame camera!)....
At f4, the 50mm Canon is at least equalled by the other Canon offerings, all scoring in the 1900s for C, 1800s for E...though the Canon 100mm starts to lose its edges very slightly..it ony does edges marginally better than the Sigma as apertures decrease.
As you might expect, the Canon 85mm maintains the low 1900s in C and high 1800s in E to f8. Very sharp indeed.
Her's another thing...the Canon 85mm has the worse chromatic aberration of the lot(Sigma best) ,and it degrades the smaller the aperture size.
Bombshell time.
OK, my Canon 50mm, at f5.6? Yep, sharp..peaks at 2047 for C, 1936 E at f5.6.
BLAM!
The Tamron is only beaten for centre sharpness at f5.6 by the Canon 50mm.
At f4, 5.6 and f8, the Tamron is sharper than the Canon 85mm. Is this worth the extra stop, you ask?
In fact, at these apertures, apart from the above example, the Tamron creams the lot of them. Completely.
At f4, the Tamron is 1999 C, 1990 E.
At f5.6, it is 2027 C and 1967 E.
At f8, it is still 2002 C, 1957 E.
As a comparison, the Canon 85mm by f8 is 1907 C, 1855 E.....even my nifty-fifty has started to "lose" it(!) in comparison... 1891 C, 1944 E.
More subjectively, then:
The Tamron 90mm is at least the equal of all the Canons here. Even its edge at 2.8 is sharper than that of the Canon 85mm at the same aperture.
The Canon 85mm f1.8 is a consistently better lens than its 100mm macro stablemate at higher apertures, though the latter's performance at f8 beats it.
At f8, remember the Tamron beats them both.
The Sigma?
Well, it IS a good lens, giving you that 5mm more. At f8 it almost rivals the Tamron at the centre...but the Sigma's edges are a different story at wider apertures. In fact, at f4 and 5.6, the Sigma is oustripped by all others at both C and E, though it has negligible chromatic aberration...if ya want fringing, just go for the Canon 85mm! In fact, I'm reminded of the reason I replaced my Sigma 10-20(or was it 22?) with the Canon: it's...decent...it's good even, and better "value", but the Canon just crisped things up a bit more.
And that's the thing, the Sigma 105mm is decent: very good even. But when you consider it next to a Canon, the difference is noticeable(to me anyway).
BUT.
You know what gives me the most satisfaction?
Knowing that my Tamron is noticeably superior to Canon. Ohyesss.
In fact, the smugness does more than offset the (er, allegedly) inflated greed of Canon in my humble. And I got a free lens hood from Tamron.
I bought this lens after reading reviews, comparing mtf charts, line resolution and personal hands on, though the only thing I can truly say is my demonstrable experience is my personal "benchmarking" in relation to my nifty-fifty, the pleasingly sharp Canon 50mm f1.8. The one denominator is that findings of self and others are with a Canon 350D body.
And yes, I know, they are differing focal lengths!
I started my shortlist, as I wanted a sharp prime lens of around the "equivalent "of 150mm on 35mm..or like the 300mm I'm used to with medium-format. The fact that it's macro was only useful to me inasmuch as macros are reportedly inherently sharp lenses.
My list of hopefuls was:
the Tamron
Canon 85mm f1.8
Canon 100mm f2.8 macro
Sigma 105mm f2.8
Basically I lumped together all the mtfs and made up my own little "points" system for centre and edge performance at some key apertures. I really only looked at wide-open, down to f8: chances are, as I'm not using it for much macro work, I don't need to be mission-critical at tiny apertures. Also, I'm guessing that if it's holding up fine by f8, then chances are, as they say.
My Canon 50mm is sharp. Real sharp..nothing less than 1800 or so on the chart, peaking at 2047 at the centre at f5.6. Even at f2.8 we get 1869 and 1805 for centre and edge respectively. Out of all the lenses here, at f2.8 it has the best centre© and edge(E) definition of the bunch, closely followed by the Canon 85mm and the Tamron.
However, notice here that whereas the Canon 85mm at f2.8 has 1866© and 1601(E), the Tamron is already only just behind at centre(1795)..yet already ahead(!) for edge definition, at 1683.
Now, the other canon(100m macro) is ALREADY at f2.8 surpassed by the Tamron for both C and E...1776 and 1670.
At his point it's interesting to note that the Sigma, whereas more free of chromatic aberration than ANY of the others, is the softest of all 4 at f2.8 and f4. The Sigma is no slouch by f5.6, giving C at 1964 and E at 1832.
Yet look at what the company is, bearing in mind that the Sigma's resolution is softening at the edges already(the Sigma's C carries on well through f8 and 11...bear in mind this will be worse on a full-frame camera!)....
At f4, the 50mm Canon is at least equalled by the other Canon offerings, all scoring in the 1900s for C, 1800s for E...though the Canon 100mm starts to lose its edges very slightly..it ony does edges marginally better than the Sigma as apertures decrease.
As you might expect, the Canon 85mm maintains the low 1900s in C and high 1800s in E to f8. Very sharp indeed.
Her's another thing...the Canon 85mm has the worse chromatic aberration of the lot(Sigma best) ,and it degrades the smaller the aperture size.
Bombshell time.
OK, my Canon 50mm, at f5.6? Yep, sharp..peaks at 2047 for C, 1936 E at f5.6.
BLAM!
The Tamron is only beaten for centre sharpness at f5.6 by the Canon 50mm.
At f4, 5.6 and f8, the Tamron is sharper than the Canon 85mm. Is this worth the extra stop, you ask?
In fact, at these apertures, apart from the above example, the Tamron creams the lot of them. Completely.
At f4, the Tamron is 1999 C, 1990 E.
At f5.6, it is 2027 C and 1967 E.
At f8, it is still 2002 C, 1957 E.
As a comparison, the Canon 85mm by f8 is 1907 C, 1855 E.....even my nifty-fifty has started to "lose" it(!) in comparison... 1891 C, 1944 E.
More subjectively, then:
The Tamron 90mm is at least the equal of all the Canons here. Even its edge at 2.8 is sharper than that of the Canon 85mm at the same aperture.
The Canon 85mm f1.8 is a consistently better lens than its 100mm macro stablemate at higher apertures, though the latter's performance at f8 beats it.
At f8, remember the Tamron beats them both.
The Sigma?
Well, it IS a good lens, giving you that 5mm more. At f8 it almost rivals the Tamron at the centre...but the Sigma's edges are a different story at wider apertures. In fact, at f4 and 5.6, the Sigma is oustripped by all others at both C and E, though it has negligible chromatic aberration...if ya want fringing, just go for the Canon 85mm! In fact, I'm reminded of the reason I replaced my Sigma 10-20(or was it 22?) with the Canon: it's...decent...it's good even, and better "value", but the Canon just crisped things up a bit more.
And that's the thing, the Sigma 105mm is decent: very good even. But when you consider it next to a Canon, the difference is noticeable(to me anyway).
BUT.
You know what gives me the most satisfaction?
Knowing that my Tamron is noticeably superior to Canon. Ohyesss.
In fact, the smugness does more than offset the (er, allegedly) inflated greed of Canon in my humble. And I got a free lens hood from Tamron.
