The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 28-80mm f3.5-5.6 and the Tamron AF 28-75mm f2.8 XR LD for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Tamron AF 28-75mm f2.8 XR LD is the longer of the two lenses at 92mm. The Tamron AF 28-80mm f3.5-5.6 with a length of 70mm is 22mm shorter. Besides being longer, the Tamron AF 28-75mm f2.8 XR LD also has a larger diameter of 73mm compared to Tamron AF 28-80mm f3.5-5.6's 72mm diameter.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Tamron AF 28-80mm f3.5-5.6 weighs 237g, which means it is 273g (53%) lighter than the Tamron AF 28-75mm f2.8 XR LD which has a weight of 510g.
Below you can find the dimension and weight table of the 'Standard Zoom Lenses in Pentax KAF Mount for size comparison purposes.
Standard Zoom Lenses in Pentax KAF Mount for Size Comparison
Lens Mounts
Both Tamron AF 28-80mm f3.5-5.6 and Tamron AF 28-75mm f2.8 XR LD has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax KF, Pentax K-3 III and Pentax K-1 II.
Tamron AF 28-80mm f3.5-5.6 is also available in Canon EF , Nikon F (FX) and Sony Alpha mounts.
Tamron AF 28-75mm f2.8 XR LD is also available in Canon EF , Nikon F (FX) and Sony Alpha mounts.
Focal Range
Tamron AF 28-80mm f3.5-5.6 has a focal range of 28-80mm and 2.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 42 - 120mm.
Tamron AF 28-75mm f2.8 XR LD has a focal range of 28-75mm and 2.7X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 42 - 112.5mm.