ZOOMINGC

To zoom in or out, simply turn the zoom ring until the desired composition is tramed on the focusing screen. The ring has a four-position scale showing which of five focat lengths—25mm, 28mm, 35mm, 40mm and 50mm—is in use in case you want to preset the lens to any of these focal lengths.

Caution: Slight vignetting will occur when you shoot with the lens at a small aperture, at its closest focusing distance and at a wide angle focal length.

DEPTH-OF-FIELD SCALE

Unlike other Nikkor lenses, the Zoom-Nikkor 25-50mm f/4 has no color-coded depth-of-field indicators engraved on the lens barrel. However, you can still determine the depth of field by using the scales provided with this pamphlet. To use, first cut out the scales along the lines indicated. Then, place the sub- ject-distance scale (B) over the depth-of-field scale (A) with the top edge of ihe

(B)scale lined up with the focal length in use and the focused distance aligned with the (A) scale's central indicator line. Now read off the numbers (on the B scale) which appear opposite the pair of depth-of-field lines (on the A scale) corresponding to the aperture in use; these numbers express the depth of field lor the settings in use.

For example, if the lens is prefocused at 1.5m (5 ft) with the focal length set at 35mm and the aperture at f/16, the numbers on the distance scale opposite the depth-of-field lines for the f/16 setting show that the depth of field extends from 1m (3.511) to 3m (10 It). You can also observe the depth o1 lield through the viewfinder by pressing the depth-of-field preview button on the camera.

INFRARED PHOTOGRAPHY

D

The plane of sharpest focus for infrared light is slightly more distant than its counterpart for visible light as seen through the camera viewfinder. Thus, for the sharpest focus in infrared photography, adjustments must be made. The scales provided can be used for determining the amount of adjustment via the dotted infrared compensation line included.

In the same manner as described in the "depth-of-field scale" section, match the prefocused subject distance (using the B scale) with the focal length and aperture scale central indicator line (on the A scale). The distance from the central indicator line to the dotted compensation line represents the amount of adjustment required. Now, turn the lens' focusing ring counterclockwise until the prefocused distance is shifted as prescribed on the scales.

10

Page 9 Page 11
Page 10
Image 10
Nikon Zoom-Nikkor 25-50mm f/4 instruction manual Zoomingc, DEPTH-OF-FIELD Scale, Infrared Photography
Page 9 Page 11

Zoom-Nikkor 25-50mm f/4 specifications

The Nikon Zoom-Nikkor 25-50mm f/4 is a versatile and compact zoom lens that has become a favorite among both professional photographers and enthusiasts. It was released in the 1970s as part of Nikon's F series lenses, designed primarily for 35mm film cameras but remaining popular in the digital age with compatible DSLR and mirrorless systems.

One of the standout features of the Nikon Zoom-Nikkor 25-50mm f/4 is its constant maximum aperture of f/4 throughout the zoom range. This capability ensures consistent exposure settings and depth of field control, making it an excellent choice for varied shooting conditions. The lens covers a wide focal length range, from a moderately wide 25mm to a standard 50mm, enabling photographers to capture a variety of scenes—from expansive landscapes to intimate portraits.

The lens incorporates several advanced optical technologies designed to enhance image quality. The construction includes multiple elements arranged in groups, effectively minimizing distortion and aberrations typically associated with zoom lenses. Nikon's proprietary Super Integrated Coating (SIC) further reduces flare and ghosting, resulting in impressive color accuracy and contrast.

Another significant characteristic of the Zoom-Nikkor 25-50mm f/4 is its compact and lightweight design. Weighing merely 600 grams, it offers portability without sacrificing durability. The lens barrel is made from high-quality materials, ensuring reliability in various shooting environments. The design also features a smooth zoom mechanism that allows for precise framing adjustments.

Focusing is made easy with the lens's close focusing capability, allowing for effective close-up work. The focus ring operates smoothly, allowing photographers to fine-tune their shots accurately. Additionally, the lens is compatible with Nikon's extensive range of accessories, including filters and hoods, enhancing its versatility.

In conclusion, the Nikon Zoom-Nikkor 25-50mm f/4 remains a trusted companion for photographers seeking a reliable zoom lens that combines excellent optical performance with practicality. With its constant aperture, superior coating technologies, and robust design, it is a perfect choice for anyone wanting to explore the art of photography, making it an enduring classic in the world of photography lenses.
Top Page Image Contents