Sigma 77mm WR Ceramic Protector Filter: Sigma
77mm WR Ceramic Protector Filter is a
lightweight, durable and thin filter constructed from clear glass ceramic
material which is
ideal for protective lens filters. In conventional high-strength protective
chemically strengthened glass is used but only the surface is strengthened. This
Ceramic is made with a special heat treatment that precipitates microcrystals
throughout, for consistent strength. It combines greater elasticity for
absorbent resistance and is also resistant to cracking from scratches or
The anti-static water repellent coating prevent water and oil from adhering to the filter
which helps to minimize ghosting and flare. It reflects 0.24% of light and
giving an overall
transmittance value of 99.76%. It features Vickers hardness number of 700HV
which make it
both scratch and shock resistant. It is included with hard acrylic case protect
when not in use. It also guards the front
lens element from impacts and
affecting image quality.
Features: Sigma 77mm WR Ceramic Protector Filter
Guards the front lens element from impacts and scratching without affecting image quality.
Clear glass ceramic is highly durable substrate, greater hardness than chemically- strengthened glass and more flexibility than sapphire crystal glass.
Features Vickers hardness number of 700HV, making it both scratch- and shock-resistant.
Clear glass ceramic involves a heat treatment process that precipitates microcrystals of a mineral called spinal in order to achieve consistent, even strength across the entire filter surface.
Anti-static Water-repellent (WR) coating prevent water and oil from adhering to the filter surface, helps to minimize ghosting and flare.
Reflects 0.24% of light, giving an overall transmittance value of 99.76%.
Included hard acrylic case protects the filter when not in use.