At Photokina this week, Sigma has announced a revamping of their lens business and three new lenses. From the release, Sigma will be grouping their lenses into Contemporary, Art and Sports. Reasons for the distinctions are not completely clear and as at this writing even the websites for Sigma country sites and distributors were not yet updated.
All the lenses have a new cosmetic look and ostensibly have improved weather sealing.
I think Contemporary is set to cover all-around use lenses, including multi-purpose zooms. Sigma has updated a number of lenses this year including their popular 18-250 walk around zoom, but cosmetically the lenses did not change much and optically the changes were nominal. This week they have announced a new 17-70 f2.8-4 lens. It's on their DC construction line so targeted at crop sensor bodies. There are lots of those out there, but I am disappointed that the lens is not a DG given the industry trend to full frame sensors.
Construction comprises aspherical, FLD (fluorite) and SLD (super low dispersion) elements in addition to traditional optical glass. It will weigh about 1 pound and take 72mm filters. A 7 blade rounded diaphragm should provide pleasing bokeh when shot wide open. Pricing was not available in the announcement.
Credit to Sigma for including performance charts with their announcement. The chart shows mild barrel distortion at the wide end and minuscule pincushion distortion at the telephoto end. Given that this lens is for crop sensors of varying mounts, probability is that an oversize image circle will make the distortion invisible in real world applications.
Sigma says that this line is targeted for artists. I think that this means fast primes. The lens announced in this group is a 35mm f/1.4 Sigma has successfully proven their ability to make superb fast primes already with the industry choice 50mm f/1.4 and their 85mm f/1.4. I've shot the 50mm and think it is better than Canon's less expensive 50/1.4. Fashion professional Lindsay Adler is a spokesperson for the 85/1.4. Thus I am optimistic about the image performance of the new 35mm. This lens is a DG mount so suitable for full frame use.
Construction comprises aspherical, FLD (fluorite) and SLD (super low dispersion) elements in addition to traditional optical glass. It's pretty large and take 67mm filters, weight was not included in the specs. A 9 blade rounded diaphragm should provide pleasing bokeh when shot wide open. Pricing was not available in the announcement.
Sigma's performance charts show negligible distortion, which is expected given the longevity of 35mm construction and the simple design it requires. Vignetting is not insignificant wide open but it will take real world tests to see how much of a difference it really makes.
Many photographers have loved the second generation of Sigma's 120-300/2.8 fast telephoto zoom. The 2nd gen model added optical image stabilization enhancing the value proposition substantially even over Sigma's really excellent 300/2.8. We see the third generation of the 120-300/2.8 in this announcement and it has changed both cosmetically and physically. The new lens is much sleeker that it's predecessor and now includes focus control buttons near the front element as we would find on Nikon and Canon super telephotos. This allows the photographer direct control of focus tracking and motor speed.
The lens is built with FLD and SLD elements as well as regular optical glass as was the predecessor. Distortion charts are available and show negligible distortions. Since the lens is an all telephoto zoom, this makes for simpler and more robust construction. No weight is given, but if the 2nd gen is an indicator, hand-holding will be a tiring proposition. A tripod foot and carry case are to be included with the lens. Filter size remains an enormous 105mm so you'll be doing a special order on that from Sigma as well.
While I am impressed with what was announced, I am looking forward to more detail and seeing the real things in stores.