Sigma’s new line of filters will ship end of January. The heat treated WR Ceramic Protective Filter line are 300% stronger, 30% lighter and water repellant.
A protective filter by definition should not influence your image – no loss in sharpness, no reduction in light, no additional flare; their fundamental & sole use is to protect the front element of your lens.
Lenses like the Canon L Series EF line also often rely on a protective filter to complete their weather sealing attributes.
The new clear glass ceramic line from Sigma boast a much tougher and flexible element that’s up to 300% stronger than previous filters as well as 30% lighter; the above science class-esque video with soothing voiceover was posted earlier in the month and does a good j0b in displaying how the technology is put to use.
I must admit I rarely use a protective filter on my lenses. I have one in my kit bag for what I bill “precarious shots” (hanging out of a car, shooting in the rain, near a waterfall) where added protection/weather sealing is required, but the standard format for me is a naked front element. This is usually down to the fact that I haven’t found a protective filter that doesn’t completely un-influence the image; I’d be keen to see how these hold up.
The Sigma WR Ceramic Protective Filter line come in a variety of sizes: 67, 72, 77, 82, 86, 95, and 105mm. I’d recommend anyone building a lens collection to pick a large filter diameter and step all lenses to that size. This is cheaper in the long run for selecting filters and makes switching out centre caps much faster.
Specs for the Sigma WR Ceramic Protective Filters:
Type: Clear protector filter
Effect Protects front lens element
Size: 67, 72, 77, 82, 86, 95, and 105mm
Filter Factor: 1 (0 stop)
Multi-Coated Water-repellent coating
Construction: Clear glass ceramic
The filters should ship by the end of January, and for price reference a 77mm version is $118, check out the full list here as well as pre-order.