SH-PMC broadband coatings of 8 layers per side for the higest reflection reduction (below 0.2%)
Dust and moisture repellent top coating on each side for easy cleaning and longest life
Constructed from Schott glass for optical clarity
Brass filter ring helps to prevent jamming and provides additional strength
The Heliopan 72mm High Transmission Circular Polarizer SH-PMC Filter will pass 99.8% of the light passing through it with only a 1-stop loss of light and with no color change to the image. In addition, their highly regarded SH-PMC 16-layer multi-coating (8-layers on each side) gives the filter an edge when it comes to durability, flare reduction as well as dust and moisture-resistance. Circular polarizers are specifically designed for use with auto-focus SLR cameras (They will also work on manual systems without problems) Same polarizing effect as regular polarizing filters that lose more light - High-Transmission design has a filter factor or 2.0 (loses only 1-stop of light) as compared to 2.5 of a traditional polarizers. The effect of the filter is greatest at a 90° angle to the sun. A circular polarizer differs from a linear polarizer in that it supports full use of a camera's autofocus and auto exposure functions.