SIGMA 20mm F2
DG DN | Contemporary
• Série I - Objectifs compacts pour des hybrides plein format modernes
• Résultats ultra-nets et à fort contraste
• Qualité de fabrication exceptionnelle de la Série I, entièrement en métal
• Objectif grand angle net, rapide et robuste
| Ligne | Contemporary |
|---|---|
| Klevu Image | /p/r/product_img01_2.png |
| Formule optique | 13 elementen (1 FLD, 1 SLD en 3 asferische lenselementen) in 11 groepen |
| Lens Type | Wide Angle |
| Sensor Size | Full Frame |
| Angle de vue | 94.5° |
| Diaphragme | 9 (afgerond diafragma) |
| Ouverture minimale | F22 |
| Distance minimale de mise au point | 22cm |
| Rapport de reproduction maximal | 1:6.7 |
| Dimensions (diameter x length) | L-Mount |
| Diamètre de filtre | 62 |
| Edition number | 22 |
LENS CONSTRUCTION
GEOMETRICAL MTF Chart
DIFFRACTION MTF CHART
Inner focus system
To increase stability, this lens configuration uses movable internal lens elements that adjust focus without changing the length of the lens barrel.
Stepping Motor
The lens is capable of smooth, quiet and high-speed AF made possible by a stepping motor, as well as supports Face/Eye Detection AF and video AF.
Nano Porous Coating
The super multi-layer coating is combined with SIGMA's unique coating technology "NPC (Nano Porous Coating)". The lens has been designed to be less susceptible to strong incident light such as backlight.
"NPC (Nano Porous Coating)" incorporates porous silica as the coating material. The porous silica layer has nano-sized holes with air inside. Having holes of this size enables a large reduction in the refractive index, allowing the reflectance to be lowered more than conventional anti-reflective coatings. As a result, reflected light causing flares and ghosting is sharply reduced, achieving clear image quality.
Super Multi-Layer Coating
SIGMA's own Super Multi-Layer Coating suppresses flare and ghosting by preventing reflections with in the lens. All lenses in the current SIGMA range feature this original technology. In digital cameras, flare and ghosting may also be caused by reflections between the image sensor and lens surfaces. Here too, SIGMA's Super Multi-Layer Coating is highly ef fective, assuring images of outstanding contrast.
Aperture ring
Aperture ring, designed to help users work intuitively
Focus Mode Switch
Using this swich, it is possible to switch the focus mode between AF and MF.
Linear focus / Non-linear focus (for L-Mount only）
A focus movement method of interchangeable lenses for mirrorless cameras (DN lens) in relation to the rotational angle of the focus ring during manual focusing.
With "non-linear focus," the amount of focal point movement varies depending on the focus ring rotational speed.
With linear focus, if the focus ring rotational angle is the same, the amount of focal point movement remains the same regardless of the focus ring rotational speed.
Mount with Dust and Splash Resistant Structure
The lens mount incorporates rubber sealing to protect the mount from dust and water drops.
Compatible with Lens Aberration Correction
Matching the optical characteristics of the lens, this function performs in-camera corrections of peripheral illumination, chromatic aberrations, distortion, and more, to further enhance image quality.
*Function available on supported cameras only. Available corrections or auto correction functionality may vary depending on the camera model.
*On cameras where lens aberration correction is controlled with 'ON' or 'OFF' in the camera menu, please set all aberration correction functions to 'ON'(AUTO).
Lens construction: 13 elements in 11 groups, with 1 FLD, 1 SLD and 3 aspherical lens elements
Compatible with high-speed autofocus
Support DMF and AF+MF
Petal-type lens hood（LH656-03）
Magnetic metal lens cap（LCF62-01M）
Compatible with SIGMA USB DOCK UD-11 (sold separately / for L-Mount only)
Designed to minimize flare and ghosting
Every single lens undergoes SIGMA’s proprietary MTF measuring system
9-blade rounded diaphragm
High-precision, durable brass bayonet mount
