The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 300mm f6.3 and the Tamron 18-200mm f3.5-6.3 III VC 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 18-200mm f3.5-6.3 III VC is the longer of the two lenses at 97mm. The Samyang 300mm f6.3 with a length of 74mm, is 23mm shorter. Besides being longer, the Tamron 18-200mm f3.5-6.3 III VC also has a larger diameter of 68mm compared to the Samyang 300mm f6.3's 65mm 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. Samyang 300mm f6.3 weighs 260g, which means it is 200g (43%) lighter than the Tamron 18-200mm f3.5-6.3 III VC which has a weight of 460g.
Filter Threads
The Samyang 300mm f6.3 has a filter size of 26mm whereas the Tamron 18-200mm f3.5-6.3 III VC has a 62mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 26mm filters that we recommend you to consider for the Samyang 300mm f6.3:
And these are the 62mm filters that we recommend for the Tamron 18-200mm f3.5-6.3 III VC:
Lens Mounts
The Samyang 300mm f6.3 has the Nikon F (DX) lens mount whereas the Tamron 18-200mm f3.5-6.3 III VC has the Sony E lens mount. Some of the latest released cameras that are compatible with these mounts are Nikon D3500, Nikon D7500 and Nikon D5600 for the Nikon F (DX) Mount and Sony ZV-E10 II, Sony A6700 and Sony FX30 for the Sony E Mount.
Samyang 300mm f6.3 is also available in the Canon EF , Four Thirds and Sony Alpha mounts.
Focal Range
Samyang 300mm f6.3 is a prime lens with fixed focal lenght of 300mm which has an effective (full-frame 35mm equivalent) focal range of
450mm when used on a APS-C / DX format camera.
On the other hand, the Tamron 18-200mm f3.5-6.3 III VC has a focal range of 18-200mm and 11.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-300mm when used on a APS-C / DX format camera.
