The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 17-55mm f2.8 IS USM and the Panasonic Leica 12-35mm F2.8 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. Canon 17-55mm f2.8 IS USM is the longer of the two lenses at 111mm. The Panasonic Leica 12-35mm F2.8 with a length of 74mm, is 37mm shorter. Besides being longer, the Canon 17-55mm f2.8 IS USM also has a larger diameter of 84mm compared to the Panasonic Leica 12-35mm F2.8'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 Leica 12-35mm F2.8 weighs 306g, 52% (339g) lighter than the Canon 17-55mm f2.8 IS USM's weight of 645g.
Filter Threads
The Canon 17-55mm f2.8 IS USM has a filter size of 77mm whereas the Panasonic Leica 12-35mm F2.8 has a 58mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 77mm filters that we recommend you to consider for the Canon 17-55mm f2.8 IS USM:
And these are the 58mm filters that we recommend for the Panasonic Leica 12-35mm F2.8:
Lens Mounts
The Canon 17-55mm f2.8 IS USM has the Canon EF-S lens mount whereas the Panasonic Leica 12-35mm F2.8 has the Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with these mounts are Canon T8i, Canon 90D and Canon SL3 for the Canon EF-S Mount and OM System OM-3 Astro, OM System OM-5 II and OM System OM-3 for the Micro Four Thirds Mount.
Focal Range
Canon 17-55mm f2.8 IS USM has a focal range of 17-55mm and
3.2X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27.2-88mm when used on a APS-C / DX format camera.
On the other hand, the Panasonic Leica 12-35mm F2.8 has a focal range of 12-35mm and 2.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 24-70mm when used on a FourThirds format camera.
