The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 180mm f3.5 LD Macro and the Canon 50mm f2.5 Macro 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 180mm f3.5 LD Macro is the longer of the two lenses at 166mm. The Canon 50mm f2.5 Macro with a length of 63mm is 103mm shorter. Besides being longer, the Tamron 180mm f3.5 LD Macro also has a larger diameter of 85mm compared to Canon 50mm f2.5 Macro's 68mm 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. Canon 50mm f2.5 Macro weighs 280g, 69% (640g) lighter than the Tamron 180mm f3.5 LD Macro's weight of 920g.
Below you can find the dimension and weight table of the 'Macro Prime Lenses in Canon EF Mount for size comparison purposes.
Macro Prime Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both Tamron 180mm f3.5 LD Macro and Canon 50mm f2.5 Macro has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Tamron 180mm f3.5 LD Macro is also available in Nikon F (FX) and Sony Alpha mounts.
Focal Range
Tamron 180mm f3.5 LD Macro is a prime lens with fixed focal lenght of 180mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides an 35mm (FF) equivalent of 288mm.
Canon 50mm f2.5 Macro is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides an 35mm (FF) equivalent of 80mm.