The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-300 F3.5-6.3 DC OS HSM and the Sony 500mm F8 Reflex 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. Sony 500mm F8 Reflex is the longer of the two lenses at 118mm. The Sigma 18-300 F3.5-6.3 DC OS HSM with a length of 102mm, is 16mm shorter. Besides being longer, the Sony 500mm F8 Reflex also has a larger diameter of 89mm compared to the Sigma 18-300 F3.5-6.3 DC OS HSM's 79mm 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. Sigma 18-300 F3.5-6.3 DC OS HSM weighs 585g, which means it is 80g (12%) lighter than the Sony 500mm F8 Reflex which has a weight of 665g.
Filter Threads
The Sigma 18-300 F3.5-6.3 DC OS HSM has a filter size of 72mm whereas the Sony 500mm F8 Reflex has a 55mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 72mm filters that we recommend you to consider for the Sigma 18-300 F3.5-6.3 DC OS HSM:
And these are the 55mm filters that we recommend for the Sony 500mm F8 Reflex:
Lens Mounts
Both the Sigma 18-300 F3.5-6.3 DC OS HSM and the Sony 500mm F8 Reflex has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A68, Sony A77 II and Sony A58.
Sigma 18-300 F3.5-6.3 DC OS HSM is also available in the Canon EF , Nikon F (DX), Pentax KAF3 and Sigma SA mounts.
Focal Range
Sigma 18-300 F3.5-6.3 DC OS HSM 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 Sony 500mm F8 Reflex is a prime lens with fixed focal lenght of 500mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 750mm.
