The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 18-400mm F3.5-6.3 VC and the Canon 18-135mm f3.5-5.6 IS STM 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. Tamron 18-400mm F3.5-6.3 VC is the longer of the two lenses at 124mm. The Canon 18-135mm f3.5-5.6 IS STM with a length of 96mm, is 28mm shorter. Besides being longer, the Tamron 18-400mm F3.5-6.3 VC also has a larger diameter of 79mm compared to the Canon 18-135mm f3.5-5.6 IS STM's 77mm 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. Canon 18-135mm f3.5-5.6 IS STM weighs 480g, 32% (230g) lighter than the Tamron 18-400mm F3.5-6.3 VC's weight of 710g.
Filter Threads
The Tamron 18-400mm F3.5-6.3 VC has a filter size of 72mm whereas the Canon 18-135mm f3.5-5.6 IS STM has a 67mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 72mm filters that we recommend you to consider for the Tamron 18-400mm F3.5-6.3 VC:
And these are the 67mm filters that we recommend for the Canon 18-135mm f3.5-5.6 IS STM:
Lens Mounts
Both the Tamron 18-400mm F3.5-6.3 VC and the Canon 18-135mm f3.5-5.6 IS STM has the same Canon EF-S lens mount. Some of the latest released cameras that are compatible with the Canon EF-S lenses are Canon T8i, Canon 90D and Canon SL3.
Tamron 18-400mm F3.5-6.3 VC is also available in the Nikon F (DX) mount.
Focal Range
Tamron 18-400mm F3.5-6.3 VC has a focal range of 18-400mm and
22.2X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
28.8-640mm when used on a APS-C / DX format camera.
On the other hand, the Canon 18-135mm f3.5-5.6 IS STM has a focal range of 18-135mm and 7.5X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 28.8-216mm when used on a APS-C / DX format camera.
