The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Panasonic 12-60mm F2.8-4.0 and the Sigma 120-400mm F4.5-5.6 DG HSM for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Sigma 120-400mm F4.5-5.6 DG HSM is the longer of the two lenses at 203mm. The Panasonic 12-60mm F2.8-4.0 with a length of 86mm, is 117mm shorter. Besides being longer, the Sigma 120-400mm F4.5-5.6 DG HSM also has a larger diameter of 92mm compared to the Panasonic 12-60mm F2.8-4.0's 68mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Panasonic 12-60mm F2.8-4.0 weighs 320g, which means it is 1320g (80%) lighter than the Sigma 120-400mm F4.5-5.6 DG HSM which has a weight of 1640g.
Filter Threads
The Panasonic 12-60mm F2.8-4.0 has a filter size of 62mm whereas the Sigma 120-400mm F4.5-5.6 DG HSM has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 62mm filters that we recommend you to consider for the Panasonic 12-60mm F2.8-4.0:
And these are the 77mm filters that we recommend for the Sigma 120-400mm F4.5-5.6 DG HSM:
Lens Mounts
The Panasonic 12-60mm F2.8-4.0 has the Micro Four Thirds lens mount whereas the Sigma 120-400mm F4.5-5.6 DG HSM has the Pentax KAF3 lens mount. Some of the latest released cameras that are compatible with these mounts are OM System OM-3 Astro, OM System OM-5 II and OM System OM-3 for the Micro Four Thirds Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF3 Mount.
Sigma 120-400mm F4.5-5.6 DG HSM is also available in Sony Alpha mount.
Focal Range
Panasonic 12-60mm F2.8-4.0 has a focal range of 12-60mm and
5.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
24-120mm when used on a FourThirds format camera.
On the other hand, the Sigma 120-400mm F4.5-5.6 DG HSM has a focal range of 120-400mm and 3.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 180 - 600mm.
