Sigma's compact constant f/2.8 standard zoom for APS-C mirrorless, a kit-lens killer.
The Sigma 18-50mm f/2.8 DC DN Contemporary launched in 2021 as a compact constant f/2.8 standard zoom for APS-C mirrorless systems. At just 290g it is remarkably lightweight for a constant f/2.8 zoom and delivers optical quality that embarrasses any kit zoom.
Optical quality is excellent with sharp results across the frame from wide open. The constant f/2.8 provides consistent exposure, shallow depth of field, and a genuine two-stop advantage over typical f/3.5-5.6 kit zooms. Stepping motor AF is fast and quiet.
Available in Sony E, Fujifilm X, and L-Mount versions. Filter thread is 55mm. The lens replaces the kit zoom for any serious APS-C mirrorless user. The Tamron 17-70mm f/2.8 Di III-A offers more range at greater size and weight.
Excellent value used. Check AF speed and accuracy, and zoom ring smoothness. This lens is the single best upgrade from a kit zoom for APS-C mirrorless. The constant f/2.8 transforms low-light capability and portrait potential.