Articles Table of Contents   Page 1: Filters for Protection, Polarization, Infrared and Ultraviolet Page 2: Tips for Buying Filters Page 3: Do Filters Degrade Image Quality? Page 4: Color balance of UV filters. Page 5: Neutral Density Filters Page 6: Filter—B+W UV 010 UV (clear) Page 7: Filter—B+W 103 0.9 ND, 3-stop neutral density Page 8: Filter—Hoya HMC Super UV 0 (clear) Page 9: Filter—B+W 091 Deep Red Page 10: Filter—B+W 092 Infrared Pass Page 11: Filter—B+W 093 Infrared Pass Page 12: Filter—Hoya R72 Infrared Pass Page 13: Filter—B+W 486 UV-IR Cut Page 14: Filter—B+W 486 Infrared Cut Page 15: Filter—Baader Venus Ultraviolet Cut Page 16: Filter—Kenko DR655 Infrared Cut Page 17: Filter—B+W 403 Ultraviolet Pass Page 18: Filter—Baader Venus Ultraviolet Pass Page 19: Filter—Baader Venus II Ultraviolet Pass Page 20: Filter—XNite BPG 750nm Infrared Bandpass Page 21: Filter—XNite BPG 830nm Infrared Bandpass Page 22: Filter—XNite BPG 950nm Infrared Bandpass

Filters overview

Filters have a variety of uses, many of which have lessened with the advent of digital camera white balance. But that doesn’t mean just any filter will do.

Even the highest quality filters can degrade image quality.

Lens protection is worthwhile in some situations, but beware of UV filters that impart a color cast by attenuating blue.

Buying filters

See the Buying Tips page.

Which type of filters?

There are only two types of filters for regular use:

• a neutral filter for lens protection (eg a “UV” or “clear” filter);
• a polarizer for reducing reflections and atmospheric haze.

A warming filter is not needed with a digital camera, since the white balance can be adjusted in the camera. Even strongly blue scenes do just fine, according to my research.

If you’re shooting a high grade lens, a quality filter usually won’t hurt, but it won’t help, unless it’s a polarizer and the goal is to cut glare, or some other particular reason, like perfect color balance.

Don’t skimp

If you’re using a filter for lens protection, don’t skimp and get a cheap filter, because even the very best filters can degrade image quality. And keep the filter spotless if you’re shooting into bright lighting.

If you have an inexpensive leans, why bother? A good quality filter can cost half as much as some basic lenses! The exception would be a cheap filter for salt spray or blowing sand, etc.

Polarizers

A polarizer is the only filter that can remove glare, or darken the sky. It can also reduce atmospheric blue haze to a limited extend, depending on the nature of the haze.

With the sky, peak polarization is at 90° from the sun, declining to 0° at 180° from the sun. For this reason, the effect can be “banding” in the sky with wide angle lenses 24mm and wider— it looks wrong, so use care.

I use a polarizer rarely, because the effect is frequently too postcard-like for my taste, a cliché I try to avoid. Use a polarizer judiciously, and remember that removing glare can make a scene look very unnatural, and can also make water look great, or fake.

Infrared and ultraviolet photography

Some types of specialty photography such as infrared or ultraviolet imaging demand specialty filters to block unwanted colors (wavelengths).

Spectral transmission measurements

Spectral transmission graphs on subsequent pages were measured by Coastal Optical Systems on specialty optical equipment using single samples of the specified filters. Graphs used by permission.