Brass made bayonet mount, Ease of use, Made in Japan

●Brass made bayonet mount

This lens incorporates a brass made bayonet mount which has both high accuracy and durability. A special treatment to reinforce its strength is applied to the surface giving it greater strength and making it highly resistant to long-term use.

●Ease of use

The new product lines incorporate rubber for the attachment part of the provided lens hood. For better usability, the design of the lens cap and AF / MF changeover switch has been improved.

●Newly developed “USB DOCK” exclusively for new product lines

Based on these new lines, we have developed special software (SIGMA Optimization Pro) that can update the lens firmware and adjust parameters such as focus.

●Evaluation with Sigma’s own MTF measuring system “A1”

We used to measure lens performance with MTF measuring system using conventional sensors. However, we’ve now developed our own proprietary MTF (modulation transfer function) measuring system (A1) using 46-megapixel Foveon direct image sensors. Even previously undetectable high-frequency details are now within the scope of our quality control inspections. The SIGMA 17-70mm F2.8-4 DC MACRO OS HSM will all be checked using this “A1” before they are shipped.

●“Made in Japan”

All Sigma's manufacturing – right down to molds and parts – is carried out under an integrated production system, entirely in Japan. We are now one of the very few manufacturers whose products are solely "made in Japan". We like to think our products are somehow imbued with the essence of our homeland, blessed as it is with clean air and water, and focused, hard-working people. We pride ourselves on the authentic quality of Sigma products, born of a marriage between highly attuned expertise and intelligent, advanced technology. Our sophisticated products have satisfied professionals and lovers of photography all over the world, because our manufacturing is based on genuine craftsmanship, underpinned by the passion and pride of our experts.