filter Questions

[WolfHeart]

I looked through the forum and see talk about a lot of different filters, BW, Haze, UV and such. I am wondering, being new and all if someone has a link or could tell me what all the initials mean and when you would use one filter over another. I would greatly appreciate it.

[Jon]

B+W is a brand, as are Hoya and Heliopan. No other brands are worth considering when it comes to screw-in (round) filters.

Multicoating glass reduces reflection at the air-glass interface and cuts down on flare and loss of contrast. Everyone has their own name for this; B+W calls it MRC; Heliopan calls it SH-PMC; Hoya has S-HMC and Pro S-HMC as their high end (they also have lesser filters).

UV and Haze filters are designed to keep UV light (which film is sensitive to) from your image. This helps contrast especially in distant shots (haze). Digital sensors are less affected by UV, so the primary role these filters play there is as protection from windblown abrasives and corrosives (sand, salt, rain, and the like) or other lens-unfriendly material. Whether you view this as important or not depends a lot on the type of photography you do. I'm often in these at-risk situations, so I use protective filters.

CPL is a circular polarizer; it essentially cuts out reflected light from non-metallic surfaces, including airborne particles. On the sky it has max. effect at right angles to the sun; on wide angle lenses this can lead to varying effects across the sky. It also costs you about 2 stops of light. Linear polarizers behave identically, except they may interfere with partially-silvered mirrors used to divert light to AF systems or, in some cameras, exposure systems.

[WolfHeart]

Thank you so Much for the info. I really appreciate it. Now i can look at filters armed with some knowledge.