The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Nikon 18-300mm F3.5-6.3G ED VR and the Tamron AF 18-250mm f3.5-6.3 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. Nikon 18-300mm F3.5-6.3G ED VR is the longer of the two lenses at 99mm. The Tamron AF 18-250mm f3.5-6.3 II LD with a length of 84mm, is 15mm shorter. Besides being longer, the Nikon 18-300mm F3.5-6.3G ED VR also has a larger diameter of 79mm compared to the Tamron AF 18-250mm f3.5-6.3 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 AF 18-250mm f3.5-6.3 II LD weighs 430g, 21% (120g) lighter than the Nikon 18-300mm F3.5-6.3G ED VR's weight of 550g.
Below you can find the dimension and weight table of the SuperZoom Lenses in Nikon F (DX) Mount for size comparison purposes.
Super Telephoto Lenses in Nikon F (DX) Mount for Size Comparison
Filter Threads
The Nikon 18-300mm F3.5-6.3G ED VR has a filter size of 67mm whereas the Tamron AF 18-250mm f3.5-6.3 II LD 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 67mm filters that we recommend you to consider for the Nikon 18-300mm F3.5-6.3G ED VR:
And these are the 62mm filters that we recommend for the Tamron AF 18-250mm f3.5-6.3 II LD:
Lens Mounts
Both the Nikon 18-300mm F3.5-6.3G ED VR and the Tamron AF 18-250mm f3.5-6.3 II LD has the same Nikon F (DX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (DX) lenses are Nikon D3500, Nikon D7500 and Nikon D5600.
Tamron AF 18-250mm f3.5-6.3 II LD is also available in Canon EF , Sony Alpha and Pentax KAF mounts.
Focal Range
Nikon 18-300mm F3.5-6.3G ED VR has a focal range of 18-300mm and
16.7X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-450mm when used on a APS-C / DX format camera.
On the other hand, the Tamron AF 18-250mm f3.5-6.3 II LD has a focal range of 18-250mm and 13.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-375mm when used on a APS-C / DX format camera.