The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 17-50mm f2.8 XR II VC LD and the Canon 18-55mm f3.5-5.6 IS 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 17-50mm f2.8 XR II VC LD is the longer of the two lenses at 95mm. The Canon 18-55mm f3.5-5.6 IS with a length of 70mm, is 25mm shorter. Besides being longer, the Tamron 17-50mm f2.8 XR II VC LD also has a larger diameter of 80mm compared to the Canon 18-55mm f3.5-5.6 IS's 69mm 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 18-55mm f3.5-5.6 IS weighs 200g, 64% (370g) lighter than the Tamron 17-50mm f2.8 XR II VC LD's weight of 570g.
Filter Threads
The Tamron 17-50mm f2.8 XR II VC LD has a filter size of 72mm whereas the Canon 18-55mm f3.5-5.6 IS 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 72mm filters that we recommend you to consider for the Tamron 17-50mm f2.8 XR II VC LD:
And these are the 58mm filters that we recommend for the Canon 18-55mm f3.5-5.6 IS:
Lens Mounts
The Tamron 17-50mm f2.8 XR II VC LD has the Canon EF lens mount whereas the Canon 18-55mm f3.5-5.6 IS has the Canon EF-S 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 Mount and Canon T8i, Canon 90D and Canon SL3 for the Canon EF-S Mount.
Tamron 17-50mm f2.8 XR II VC LD is also available in Nikon F (DX) mount.
Focal Range
Tamron 17-50mm f2.8 XR II VC LD has a focal range of 17-50mm and
2.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27.2-80mm when used on a APS-C / DX format camera.
On the other hand, the Canon 18-55mm f3.5-5.6 IS has a focal range of 18-55mm and 3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 28.8-88mm when used on a APS-C / DX format camera.