Sigma announces not one, but two supertele zoom lenses

The Japanese lensmaker has been giving Canon and Nikon serious competition for SLR lenses with recent high-end models like the 35mm f1.4 DG HSM, 50mm f1.4 DG HSM and 18-35mm F1.8 DC HSM . But the 150-600mm models more directly compete with a supertele zoom from its main rival in the third-party lens market, Tamron.

Sigma's two lenses are geared for different customers. The 150-600mm F/5-6.3 DG OS HSM Sports has "professional-grade optics and greater durability for challenging, high-action photographic situations," Sigma said, whereas the 150-600mm F/5-6.3 DG OS HSM Contemporary is a bit smaller, lighter and geared more for enthusiasts than pros. Both will be available for Sigma, Canon and Nikon mounts.

Tamron announced its SP 150-600mm F/5-6.3 Di VC USD a year ago and now sells it for about $1,069 and £999 in the UK. The Sigma Sports version will cost $2,000 (£1,600, AU$2,200) -- if that's too rich for you the company's 150-500mm version is now down to less than $900 (£1,000, AU$1,000) -- and will be available in October 2014.

Supertelephoto zoom lenses are expensive and bulky, but they're popular among wildlife and sports photographers who can't get close to their subjects. High-end pro models from Canon and Nikon can cost thousands of dollars, and more than $10,000 in some cases. The competition from Sigma and Tamron don't carry such a price tag, but with narrower apertures, they also aren't as good at capturing images of moving subjects like racing motorcycles or twitchy birds.

Also in conjunction with the Photokina show in Cologne, Germany, next week, Sigma announced a $579 price and October availability for its new 18-300mm F/3.5-6.3 DC Macro OS HSM Contemporary. These ultrazooms are convenient for travelers and people who don't want to change lenses often, but there's no free lunch: they invariably have lesser image quality compared to shorter-range zooms.

Sigma also announced two new teleconverters -- adapters that extend telephoto range, though they allow less light through and degrade some image quality some. The $349 190g TC-1401 extends range by 1.4x and cuts aperture by one f-stop (so a 200mm f4 lens would become a 280mm f5.6, for example) and uses one special low dispersion (SLD) glass element for better optical quality. The $399 290g TC-2001 doubles telephoto range and cuts aperture by two f-stops. The company didn't announce when the teleconverters would be available.

Some details of the lenses:

• The 150-600mm Sports model is splashproof and dustproof, has 24 lens elements in 16 groups. Of those elements, three are SLD glass and two are FLD glass, which Sigma says performs as well as higher-priced fluorite crystals. It's got a close-focus distance of 2.6m (102.4 inches), measures 12.2cm (4.8in) wide by 29cm (11.4in) long, and weighs 2,860g (100.9 ounces).
• The 150-600mm Contemporary model has 20 elements, including one FLD and three SLD, in 14 groups. It's got a close-focus distance is 280cm (110.2in) and measures 10.4cm (4.1in) wide by 25.9cm (10.2in) long. Sigma hasn't yet determined a final weight.
• The 18-300mm model has four FLD elements and one SLD element. It's designed for lower-end to midrange SLRs with APS-C-sized image sensors, on which its focal length is the equivalent of about 27-450mm. Its close-focus distance of 38.1cm (15in) enables a 1:3 magnification, but a $55 AML72-01 lens that can be paired with it brings the magnification up to 1:2.