Αντιγράφω από το 16-9.net (ιστοσελίδα για τους Canonάκηδες που δεν έχουν κόμπλεξ προς τις άλλες εταιρείες φακών). Ποιος είναι ο καλύτερος ευρυγώνιος ζουμ για full-frame.
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What's the best wide angle zoom?
Short Answer:
1. Contax N 17-35mm f2.8
2. Nikon 17-35mm f2.8 AFS
3. Leica 21-35mm f3.5-4 / Canon 16-35mm L f2.8
4. Sigma 15-30mm
5. Sigma 12-24mm
6. Tamron 17-35mm
Long Answer:
It depends. If you can focus properly without AF in the 17-24mm range (the difficulty of which is not to be underestimated), the Contax, Nikon and Leica zooms all offer something more than the Canon L can deliver.
If we consider resolution, the Nikon is better than the Canon from f5.6 to f16, but the Canon L is better from f2.8 to f4. All require stopping down to f8 for critically sharp corners. The Nikon is sharper than the Canon from 17-25mm; the Canon is at least as good from 26-35mm. The Leica is sharper than the Canon and the Nikon from 24mm to 35mm, but not from 21-23mm. The Sigma 15-30mm is amazingly sharp centre frame at almost all apertures, but can't render a sharp corner at any of them. The Tamron has better corners, but isn't as crisp centre frame.
If we consider distortion, the Sigma 12-24mm is impeccable throughout. The Leica is well controlled: neutral in the 21-24mm range and pincushion from 24mm up. The Nikon has fairly strong barrel distortion in the 17-19mm range, is dead neutral from 20-22mm, and pincushion from 23mm up. The Canon and Sigma 15-30mm are similar. The Tamron is spoilt by extreme waveform distortion at a wide range of focal lengths.
If we look at chromatic aberration, the Sigma 12-24mm and Contax excel. The Canon, Nikon and Sigma zooms all suffer to a similar degree at all apertures. The Tamron is very poor in this regard.
Heading into more subjective realms, the Nikon renders blues particularly attractively, with a neutral colour balance and fine microcontrast. The Contax has a vivid drawing style with all the typical Zeiss virtues of 'believable' 3D rendering and punchy, saturated colours. The Leica is also typically on-brand, with open shadows, true colouring and high resolution in the 24mm-35mm range. The Canon also handles colour well, without obvious cast, but the images don't have the intangible magic and sparkle of the more 'exotic' glass. Both Sigmas are what one might might politely call 'warm' (ie, yellow) – the 15-30mm is marginally worse than the 12-24mm."
Αυτά στο FF. Στη 40D μου ο 15-30 σε ανάλυση ισοφαρίζει και στο κέντρο φτάνει να ξεπερνά τον 17-35/2.8 της Νίκον -τους έχω αμφότερους.