Etch Vwvwsigmaimagiimgukcom

EISA gave this lens its European Lens of the Year Award for 2004-5 on account of the zoom's impressve 12mm minimum focal length and compatibility with both full-frame anc APS-C cameras.

Being a full-frame zoom this lens is larger than its APS-C (DC) stablemate: further bulk comes from the non-removable petal-shaped lens hood, which needs an adaptor-collar to be slid oyer it before the lens cap can be fitted. It is not clear why Sigma hasn't simply supplied a bespoke slip-on lens cap. It is true tha: the lens cap and adaptor can beslipped-off as a single item but they then tend :o separate: if I owned this lens I'd be tempted to glue the lens cap to the adaptor!

The fixed lens hood also means filters cannot befitted to the front of the lens so Sigma has helpfully provided a gelatine slot at the rear. Users who are not accustomed to fitting gelatins may find it rather awkward and should move the lens to its 24mm setting to avoid touching the rear element. Regardless of dexterity, polarising filters are out of the question as they cannot be rotated.

These niggles aside, the optic handles very well. The forward manual-focusing ring is available at all

excellent. The MTF curves obtained for maximum and intermediate focal lengths are so well matched that they are indistinguishable" the 12mm curve is slightly lower but, apart from a distinct dip at f/4, it remains above the critical 0,25 cycles-per-pixel level right out to f/16.

Significant chromatic aberration is evident at 12mm, caused by a distinct separation of the blue curve, but visually (and in real-world pictures) Tokina's zoom produces some very pleasing images that are virtually free from im perfections.

The fact that the lens is only offered n Canon and Nikon mounts may disappoint some, but the Tokina handles very nicely and can fairly be described as a joy to use.

times in AF mode (on Canon, Nikon and Sigma cameras) and is nicely geared for accurate use: the rearward zoom ring requires a slight shift of grip but again has a very pleasing feel. Automatic focusing is carried out internally so there is no need to keep fingers clear ot the tocusmg ring. A distance window is provided together with depth-of-field markings for both maximum and minimum focal-length settings. Though it is not evident from the resolution curves, there is some colour fringing at the 12mm setting but the effect is slight.

Overall, full-frame users will enjoy this lens but APS-C cameras are better served by its DC sibling, which offers better performance at a lower price.

0 0

Post a comment