Sigma 18-35mm f/1.8 DC HSM
World's first zoom lens with a f/1.8 aperture
Lens Mount: APS-C
Construction: 17 elements, 12 groups
Filter Thread: 72mm
This lens is unique for the way it's the first ever zoom to offer constant f/1.8 aperture. It bears Sigma's new elite "A" badge to indicate its premium design and produces no signs of colour fringing whatsoever. Distortion is equally well controlled, with just a hint of barrel curavature at 18mm, converting to an equally negligible amount of pincushion distortion at 35mm.
Canon EF 24-105mm f/4L IS USM
Features a 3-stop Image stabilizer
Lens Mount: EF/EF-S
Construction: 18 elements, 13 groups
Filter Thread: 77mm
Often considered as the first choice lens for Canon full-frame users, this pro-spec L-Series optic is solid and robustly built.
Autofocus is brisk and quiet, while it produces a near-total absence of chromatic aberration. Sharpness levels can't be faulted and though it has a maximum aperture of f/4, it's a lens that provides the perfect balance of features for the money.
Nikon AF-S 24-120mm f/4G ED VR
Built to withstand heavy day-to-day use
Lens Mount: FX
Construction: 17 elements, 13 groups
Filter Thread: 77mm
Designed for Nikon FX-format DSLRs, this optic features a Silent Wave Motor for near-silent AF and a twin-mode Vibration Reduction (VR) system to counteract handshake. Optically, it's a very strong performer too. It's completely free of chromatic aberrations at both ends of the zoom and boasts a sweet-spot of focus that's found between f/5.6-8.
Panasonic G X Vario 12-35mm f/2.8 Power O.I.S.
Super lightweight performer for CSCs
Lens Mount: MFT
Construction: 14 elements, 9 groups
Filter Thread: 58mm
This lens has a dustproof and splashproof design and offers the same coverage as a 24-70mm full-frame lens. Technical testing revealed some chromatic aberration set to the shorter side of its focal length, but this aside, it produces an outstanding set of MTF curves and backs this up with a rock-solid feel that shouts premium quality in the hand.