Basic Photography Course

haze filter includes contrast and correction filters. When

contrast and correction filters are used for haze
penetration, they may be considered special-purpose
filters. Although contrast filters can be used for cutting
haze, these filters affect the gray tone rendering of
colored objects. The contrast and correction filters that
absorb the shorter wavelengths are the most effective.
The recommended contrast and correction filter colors,
in the order of greatest to least effective for haze
penetration, are as follows:

Red

Orange

Yellow

Green

The use of an infrared sensitive black-and-white

film with an infrared filter provides the greatest haze
penetration of all. Special, visually opaque infrared
filters completely absorb the scattered ultraviolet
radiation and the visible light that produce haze. This
absorption by an infrared filter allows the scene to be
photographed entirely with unscattered infrared
radiation. An infrared sensitive black-and-white film

without an infrared filter, or at least a red contrast filter,
is not effective for haze penetration. Infrared
black-and-white film is sensitive to ultraviolet radiation,
violet, and blue light as well as infrared radiation and
red light. The gray tone rendering of a colored subject
in a black-and-white print produced from an infrared
negative is greatly distorted or contrasty.

The visually opaque infrared filters are identified by

numbers as follows:

87A

87B

87C

88A

89B

When the effect of haze is to be reduced with an

equal change to the gray tone rendering of all colored
objects in a black-and-white print, filters that primarily
absorb ultraviolet (UV) radiation are required. These

filters have a very pale pink or yellow tint and may be
identified by numbers as follows:

Colorless haze or ultraviolet absorbing filters are

often used to protect the front element of a lens from
damage. It is much cheaper to replace a filter than it is
to repair or replace a lens.

The polarizing filter is another type of special-

purpose filter that can be used to reduce the effects of
haze.

POLARIZING FILTERS

Polarizing filters look like gray neutral density

filters. However, their effect becomes apparent when
you look at the blue sky through a polarizing filter while
rotating it. As you rotate the filter, the sky appears to get
darker, then lighter.

Polarizing filters are used in black-and-white and

color photography for the following reasons:

1. Reduction or elimination of unwanted

reflections (glare) from nonmetallic surfaces, such as
glass and water

2. Exposure control, similar to ND filters

3. Reducing the effects of haze

4. Darkening the blue-sky image in both black-

and-white and color photography

5. Increasing color saturation in a color photograph

without altering the hues of image colors

As discussed in chapter 1 of this training manual,

the term polarize refers to a property of light that cannot
be seen-the direction in which light rays vibrate.
Unpolarized light rays vibrate in all directions at right
angles to the ray itself. A light ray is polarized when
vibrations are in one direction only.

Any synthetic material that polarizes light may be

called a polarizer, or polarizing device. A polarizing
screen is a polarizer in sheet form.

There are a number of different polarizing filters.

However, there are only two main types: one type fits
over the camera lens and the other is designed to be used
over a light source. Since they do not affect color,
polarizing filters and screens may be used for both
black-and-white and color photography. A polarizing
device used over the camera lens may have small posts
(known as indicator handles) projecting from the rim for
aligning the axis of the polarizing grid.

3-8

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Basic Photography Course

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DOFMaster for Windows On-line Depth of Field Calculator DOFMaster for Mobile Devices On-line Depth of Field Table Hyperfocal Distance Chart Articles FAQ Recommended Books Support Contact Links Home As an Amazon Associate I earn from qualifying purchases.	contents <- previous page next page -> haze filter includes contrast and correction filters. When contrast and correction filters are used for haze penetration, they may be considered special-purpose filters. Although contrast filters can be used for cutting haze, these filters affect the gray tone rendering of colored objects. The contrast and correction filters that absorb the shorter wavelengths are the most effective. The recommended contrast and correction filter colors, in the order of greatest to least effective for haze penetration, are as follows: Red Orange Yellow Green The use of an infrared sensitive black-and-white film with an infrared filter provides the greatest haze penetration of all. Special, visually opaque infrared filters completely absorb the scattered ultraviolet radiation and the visible light that produce haze. This absorption by an infrared filter allows the scene to be photographed entirely with unscattered infrared radiation. An infrared sensitive black-and-white film without an infrared filter, or at least a red contrast filter, is not effective for haze penetration. Infrared black-and-white film is sensitive to ultraviolet radiation, violet, and blue light as well as infrared radiation and red light. The gray tone rendering of a colored subject in a black-and-white print produced from an infrared negative is greatly distorted or contrasty. The visually opaque infrared filters are identified by numbers as follows: 87 87A 87B 87C 88A 89B When the effect of haze is to be reduced with an equal change to the gray tone rendering of all colored objects in a black-and-white print, filters that primarily absorb ultraviolet (UV) radiation are required. These filters have a very pale pink or yellow tint and may be identified by numbers as follows: 2A 2B 2C 2E Colorless haze or ultraviolet absorbing filters are often used to protect the front element of a lens from damage. It is much cheaper to replace a filter than it is to repair or replace a lens. The polarizing filter is another type of special- purpose filter that can be used to reduce the effects of haze. POLARIZING FILTERS Polarizing filters look like gray neutral density filters. However, their effect becomes apparent when you look at the blue sky through a polarizing filter while rotating it. As you rotate the filter, the sky appears to get darker, then lighter. Polarizing filters are used in black-and-white and color photography for the following reasons: 1. Reduction or elimination of unwanted reflections (glare) from nonmetallic surfaces, such as glass and water 2. Exposure control, similar to ND filters 3. Reducing the effects of haze 4. Darkening the blue-sky image in both black- and-white and color photography 5. Increasing color saturation in a color photograph without altering the hues of image colors As discussed in chapter 1 of this training manual, the term polarize refers to a property of light that cannot be seen-the direction in which light rays vibrate. Unpolarized light rays vibrate in all directions at right angles to the ray itself. A light ray is polarized when vibrations are in one direction only. Any synthetic material that polarizes light may be called a polarizer, or polarizing device. A polarizing screen is a polarizer in sheet form. There are a number of different polarizing filters. However, there are only two main types: one type fits over the camera lens and the other is designed to be used over a light source. Since they do not affect color, polarizing filters and screens may be used for both black-and-white and color photography. A polarizing device used over the camera lens may have small posts (known as indicator handles) projecting from the rim for aligning the axis of the polarizing grid. 3-8 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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