The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-250mm F3.5-6.3 DC OS HSM and the Nikon 18-300mm F3.5-5.6G ED VR for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Nikon 18-300mm F3.5-5.6G ED VR is the longer of the two lenses at 120mm. The Sigma 18-250mm F3.5-6.3 DC OS HSM with a length of 89mm, is 31mm shorter. Besides being longer, the Nikon 18-300mm F3.5-5.6G ED VR also has a larger diameter of 83mm compared to the Sigma 18-250mm F3.5-6.3 DC OS HSM's 74mm diameter.
The 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. Sigma 18-250mm F3.5-6.3 DC OS HSM weighs 470g, which means it is 360g (43%) lighter than the Nikon 18-300mm F3.5-5.6G ED VR which has a weight of 830g.
Below you can find the dimension and weight table of the SuperZoom Lenses in Nikon F (DX) Mount for size comparison purposes.
SuperZoom Lenses in Nikon F (DX) Mount for Size Comparison
Lens Mounts
Both the Sigma 18-250mm F3.5-6.3 DC OS HSM and the Nikon 18-300mm F3.5-5.6G ED VR 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.
Sigma 18-250mm F3.5-6.3 DC OS HSM is also available in Canon EF , Pentax KAF3, Sony Alpha, Sigma SA, Canon EF, Nikon F (DX), Pentax KAF3, Sony Alpha and Sigma SA mounts.
Focal Range
Sigma 18-250mm F3.5-6.3 DC OS HSM 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. Nikon 18-300mm F3.5-5.6G 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.