DEPTH-OF-FIELD Indicators, Filtersc

desired focus setting, and tighten the preset ring locking screw to set the click-stop position.

DEPTH-OF-FIELD INDICATORS

Depth of field (i.e., the zone of acceptable image focus) can be checked by reading the color-coded depth-of-field indicators engraved on the lens barrel. The pairs of colored lines on either side of the white distance scale index line correspond to f/numbers of the same color on the aperture scale. You can also observe the depth of field through the viewfinder by simply pressing the depth-of-field preview button on the camera body.

FILTERSC

The Nikkor ED 800mm f/8 IF uses standard Nikon 39mm screw-in filters, mounted on a filter holder which is inserted into the body of the lens just behind the tripod mount- ing collar. To gain access to the filter holder for filter changing, press and turn the knob on the filter holder 90° counterclockwise until the white line on the knob is at right angles to the axis of the lens. The filter holder will come free and can be lifted out of the lens. Unscrew the filter and replace it with the one you wish to use. Lock the filter holder back in place by reversing the above procedure. A special filter holder is provided with this lens which accepts gelatine filters. To fit the filter, release the catch, flip open the filter plates, insert the gelatine filter, close the plates and cut off the excess with a sharp knife. The filter holder can then be mounted in the usual way. Please note that due" to a slight difference in thickness between gelatine and glass filters, some focus shift may occur when changing from one type of filter to the other; this discrepancy is easily corrected, however, by slightly shifting the focus setting. A filter must be mounted in the lens at all times.

RECOMMENDED FOCUSING SCREENS

Various interchangeable focusing screens are available for F2 and F3 Nikon cameras to suit any type of lens or picture-taking situation. Those which are recommended for use with this Nikkor ED 800mm f/8 IF lens are listed below.

^~~~~~~~~~~^^^ Screen			G2 G3 G4 HI	H2 H3 H4 J K/P		M R T
Camera ^~~~~~~~~~~^^^A/L B C D E Gl			G2 G3 G4 HI	H2 H3 H4 J K/P		M R T
F3	m © •	0 0	©	©	• m	•	•
F2	m © •	ft ©	©	©	• V	•

•When the TC-200 teleconverter is attached to this lens, use the following table*:

^ - ~ _ ^ ^	Screen	A/L	B c D E Gl		G2 G3 G4 HI H2 H3 H4 J	K/P	M R	T
Camera		A/L	B c D E Gl		G2 G3 G4 HI H2 H3 H4 J	K/P	M R	T
F3		•	©	o o ©	•	•	•	•
F2		m ©		o o ©	•	•	•

*Vignetting or other performance deterioration may be noticeable in the im age recorded on the film.

•When the TC-300 teleconverter is attached to this lens, use the following table:

~"-—-^^^ Screen	A/L B c D E Gl				G2 G3 G4 HI H2 H3 H4	J	K/P M	R	T
Camera ^~""~~---^^	A/L B c D E Gl				G2 G3 G4 HI H2 H3 H4	J	K/P M	R	T
F3	•	©		o ft	©	•	$	•	m
F2	•	©	0	o ft	©	•	•	•

ED specifications

Nikon ED (Extra-low Dispersion) optics represent a significant advancement in lens technology, specifically designed to enhance image quality by reducing chromatic aberration and improving color accuracy. These specialized glass elements are utilized in various Nikon products, including cameras, binoculars, and telescopes, making them a cornerstone of Nikon's optical engineering.

One of the primary features of Nikon ED glass is its ability to minimize the dispersion of light as it passes through the lens. Traditional glass can produce various wavelengths of light at slightly different focal points, leading to color fringing and a loss of sharpness in photographs. By incorporating ED glass, Nikon lenses achieve better focus across the color spectrum, resulting in more precise, vibrant images with greater detail.

The use of Nikon ED glass also enhances contrast and brightness. The superior optical properties of ED elements allow for increased light transmission, ensuring that images maintain their vibrancy even in challenging lighting conditions. This capability is particularly beneficial for wildlife and landscape photographers who often work in varied environments.

Another hallmark of Nikon ED technology is its durability. Lenses equipped with ED glass are typically constructed with robust materials, making them resistant to the rigors of outdoor use. Weather-sealed designs further protect against elements such as dust and moisture, ensuring reliable performance in a wide range of conditions.

In addition to its optical benefits, Nikon ED technology also incorporates advanced coatings, such as anti-reflective coatings, to reduce lens flare and ghosting. This enhancement allows for clearer, more defined images, particularly when shooting in backlit or high-contrast situations.

Nikon's commitment to precision engineering is evident in the meticulous design and manufacturing processes involved in creating ED lenses. Each lens is crafted with stringent quality control measures, ensuring that every product meets Nikon's high standards for performance and reliability.

In summary, Nikon ED technology exemplifies the brand's dedication to delivering superior optical performance. With its unique ability to counteract chromatic aberration, enhance light transmission, and withstand various environmental conditions, Nikon ED lenses are a preferred choice for photographers seeking unparalleled image quality and durability in their optical equipment.