105mm F2.8 EX DG OS HSM Macro
LENS CONSTRUCTION
- SLD glass
MTF CHART
The MTF (Modulation Transfer Function) is one of the measurements for evaluating a lens' performance, and it shows how faithfully the contrast of the subject can be reproduced on the image plane. The horizontal axis shows the image height (distance from the center of the image in mm) and the vertical axis shows the contrast value (maximum value is 1).
The closer the 10 line pairs/mm curve is to 1, the higher the contrast and clarity of the lens is, and similarly, the closer the 30 line pairs/mm curve is to 1, the better the resolution and sharpness of the lens is.
*The MTF chart depicts the result at the wide-open aperture.
*For mirrorless lenses that support distortion correction, the horizontal axis shows the image height equivalent to when an L-Mount lens is attached to a Sigma L-Mount camera with distortion correction applied. (The effect of distortion correction may differ depending on the mount and camera used.)
*The spatial frequency indicates the variation on the image plane before distortion correction is performed.
Spatial Frequency
S: Sagittal Line
M: Meridional Line
10lp/mm
30lp/mm
DIFFRACTION MTF
Hyper Sonic Motor (HSM)
The Hyper Sonic Motor (HSM) uses ultrasonic waves to drive the autofocus mechanism. It features extremely quiet operation, high torque, and excellent focusing speed.
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.
Exclusive low-dispersion glass
Careful arrangement of exclusive low-dispersion glass elements gives SIGMA lenses superlative image rendition untarnished by residual chromatic aberration.
Other
- Rounded diaphragm
