Lots of photographers fit glass filters to the front of their lenses purely for protection. It's a lot easier and cheaper to replace a filter than it is to get a scratched or damaged front lens element repaired.
But filters can get damaged too, and if you regularly shoot in harsh, hostile environments then you should take a look at Hoya's new Fusion range.
Hoya has developed a new anti-static coating that we're told acts like a 'force field' around the filter to repel dust. This means you shouldn't need to clean them so often – and, when you do, the hardened top layer should clean more easily and resist scratching better than a regular filter. The coating is also water-repellent.
These Fusion filters also have 9 layers of Super Multi-coating to reduce surface reflections and increase light transmission. High performance optical glass has been selected to eliminate any color shifts or changes to clarity or contrast.
The Protector filter is entirely neutral and simply to offer protection to the front element of the lens. The UV filter is designed to cut out ultra-violet that adds haze to distant scenic shots and could prove particularly useful to landscape photographers.
Probably the most useful filter of the three, though, is the circular polarizer. These are best known for making blue skies even bluer, but they can also cut surface glare and reflections from glossy objects, so they're also useful for increasing colour saturation and seeing 'through' water and glass more clearly.
The filters also use a 'low-profile' aluminium frame to reduce the risk of vignetting with wide-angle lenses – thick filter mounts can sometimes appear in the corner of the frame with very wide lenses or zoom settings.
The new Hoya Fusion filters come in a range of sizes, from 37mm to 82mm and prices start at £26.99 (about US$41/AU$57) for a 37mm protector filter.