Sigma 40mm f/1.4 DG HSM A (Art) Full Frame Lens for Canon EF-Mount {82}

Sigma's 40mm f/1.4 Art built to cine-lens optical standards.

The 40mm focal length sits at an angle of view that feels more natural than a 35mm but less compressed than a 50mm, and at f/1.4 this lens gives you genuine separation from backgrounds without forcing you into a telephoto working distance. Sigma designed the 40mm Art from the ground up against cine-lens benchmarks, which meant correcting axial and magnification chromatic aberration to near-zero levels using three FLD and three SLD elements within a 16-element, 12-group formula. Distortion stays at or below 1%, and sagittal coma flare is corrected across the full frame, so point light sources at the edges of the frame don't smear into the wings you'd see on a lesser wide-aperture design.

The HSM ring-type autofocus motor is quick and silent, and the internal focusing design means the front element doesn't rotate, which matters when you're using polarizers or graduated ND filters on the 82mm thread. Full-time manual focus override lets you intervene mid-hunt without switching modes. Weather and dust sealing, plus a water- and oil-repellent front coating, mean the lens holds up in the field when conditions go sideways. A 9-blade rounded diaphragm keeps out-of-focus highlights round through most of the aperture range. At 1,200g it's not a small lens, but that weight is the cost of the optical formula that makes this one of the most rigorously corrected 40mm lenses built for Canon EF mount.

Who It's For

Portrait photographers who work wide open will appreciate how the f/1.4 aperture pairs with coma and chromatic aberration correction that keeps subjects sharp while backgrounds fall away cleanly. Environmental documentary shooters get a focal length that reads naturally on full-frame sensors without the distortion common to wider primes. Videographers feeding Canon EF glass into cinema rigs benefit from the silent HSM motor, internal focus, and optical performance that meets 8K-resolution standards. Event photographers working in mixed or low light gain a fast prime with weather sealing and AF speed capable of handling spontaneous moments.

Key Features

• 40mm focal length with f/1.4 aperture for natural perspective and background separation
• 16-element, 12-group optical formula with 3 FLD + 3 SLD elements
• Axial and magnification chromatic aberration corrected to near-zero levels
• Distortion under 1% and sagittal coma flare corrected across full frame
• HSM ring-type autofocus motor with full-time manual focus override
• Internal focusing design keeps front element stationary for filter use
• 9-blade rounded diaphragm for round bokeh through aperture range
• Weather and dust sealing with water- and oil-repellent front coating

FAQ

What makes the 40mm focal length different from 35mm or 50mm?

The 40mm angle of view splits the difference-wider than a 50mm so you're not forced into telephoto working distances, but longer than a 35mm so you avoid the wider-angle perspective compression. At f/1.4, that balance means genuine subject separation without losing the lens-to-subject intimacy.

How does the cine-lens design standard translate to still photography?

Cine lenses are built to maintain optical consistency across the entire frame during camera movement and panning, which means corrections for axial chromatic aberration, magnification chromatic aberration, and sagittal coma flare are pushed to their limits. That same rigor eliminates the edge smearing and color fringing you'd see on a lesser f/1.4 design, giving you sharp, color-accurate edge-to-edge performance.

Does the front element rotate during focus?

No. Internal focusing keeps the front element stationary, which matters for polarizers and graduated ND filters on the 82mm thread-they won't shift their effect as you focus.

How fast is the autofocus, and can you override it?

The HSM ring-type motor is fast and silent. Full-time manual focus override lets you grab the focus ring mid-hunt without switching modes or disabling AF.

What's the optical formula, and why is it so heavy at 1,200g?

16 elements in 12 groups, including 3 FLD and 3 SLD elements to correct chromatic aberrations to near-zero levels. That complexity and glass volume is what delivers distortion under 1% and the correction of coma flare across the full frame-lighter designs simply don't correct these aberrations as rigorously.

Is this lens sealed for weather?

Yes. Dust and weather sealing combined with a water- and oil-repellent front coating means it holds up in field conditions without babying.

Can you use this with third-party bodies or adapters?

The lens is Canon EF mount. It's compatible with the Sigma MC-11 mount converter if you need to adapt it to other mounts, and with the optional Sigma USB Dock for firmware adjustments to the manual focus override sensitivity.