The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 17-35mm F2.8-4 Di OSD and the Tamron 17-50mm f2.8 XR II LD 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 17-35mm F2.8-4 Di OSD is the longer of the two lenses at 93mm. The Tamron 17-50mm f2.8 XR II LD with a length of 82mm, is 11mm shorter. Besides being longer, the Tamron 17-35mm F2.8-4 Di OSD also has a larger diameter of 84mm compared to the Tamron 17-50mm f2.8 XR II LD's 74mm 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. Tamron 17-50mm f2.8 XR II LD weighs 430g, 6% (30g) lighter than the Tamron 17-35mm F2.8-4 Di OSD's weight of 460g.
Filter Threads
The Tamron 17-35mm F2.8-4 Di OSD has a filter size of 77mm whereas the Tamron 17-50mm f2.8 XR II LD 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 77mm filters that we recommend you to consider for the Tamron 17-35mm F2.8-4 Di OSD:
And these are the 67mm filters that we recommend for the Tamron 17-50mm f2.8 XR II LD:
Lens Mounts
The Tamron 17-35mm F2.8-4 Di OSD has the Nikon F (FX) lens mount whereas the Tamron 17-50mm f2.8 XR II LD has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Tamron 17-35mm F2.8-4 Di OSD is also available in the Canon EF mount.
Tamron 17-50mm f2.8 XR II LD is also available in Canon EF , Nikon F (DX) and Sony Alpha mounts.
Focal Range
Tamron 17-35mm F2.8-4 Di OSD has a focal range of 17-35mm and
2.1X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
25.5 - 52.5mm.
On the other hand, the Tamron 17-50mm f2.8 XR II LD has a focal range of 17-50mm and 2.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 25.5-75mm when used on a APS-C / DX format camera.
