Nikon Lens Terminology

Nikon has one of the most sophisticated range of cameras and lenses available from any manufacturer. Lenses range from wide angle, telephoto, micro and tilt and shift. There can be some difficulty in understanding the Nikon terminology and the following may assist to help you understand.

Nikons Lens Identifying Codes

Nikon’s Ring of Gold
Many of the Nikon lenses have a ring of Gold around the lens barrel. I do not believe there is any definitive specification from Nikon as to what this Gold ring means, apart from the fact that it is an indication that the lens is regarded as a lens suitable for professional usage.

AF Lenses

AF effectively identifies that an lens is autofocussing. Generally AF lenses are focussed from a screwdriver type connection from the camera and they do not have a focussing motor in the lens. Some of the lower range Nikon camera bodies do not have the focussing motor in the camera body and can only accept AF-S lenses.

AF-S Lenses
AF-S identifies that the lens focusses with an internal motor in the lens as distinct from being focussed by a link from the camera to the lens. AF-S lenses can also have the focussing manually controlled from the lens for fine tuning of the focus.

AI Lenses
AI lenses are automatic indexing (AI) lenses. The automatic indexing is to allow metering with the lens wide open. Earlier lenses had to be manually indexed.

AIS Lenses
AIS lenses automatic index – shutter (AIS) have a machined groove to indicate that a lens with a linear action diaphram is mounted. This information is not used on current cameras.

D Lenses
D lenses use distance encoder technology so that the lens can send the focussed distance back to the camera.

DC Lenses
DC lenses have a defocus (DC) control so that the out of focus areas of the image can be changed. This can be used for blurring out of focus areas in the image.

DX Lenses
DX lenses are designed specifically for the smaller DX inage sensor which uses a lens multiplication factor (crop factor) of 1.5 compared to the 35mm full frame sensors. To some extent thes DX lenses cam be made smaller than the comparable 35mm lenses. Some of the DX lenses do actually cover the full 35mm area over a part of the zoom range.

ED Lenses
ED lenses use extra-low dispersion (ED) glass in the lens. This coating is applied to reduce lens aberations such as chromatic aberations and ensure that all wavelengths pass through the lens and focus at the same point.

G Lenses
G lenses do not have a mechanical aperture on the lens far manual adjustment. The lens aperture is adjusted manually from a command dial on the camera.

IF Lenses
IF lenses focus the lens by moving groups of lens elements internally in the lens and this type of focussing does not extend the length of the lens as it is focussed from close up to infinity.

Micro Lenses
Micro is Nikons terminology for their macro lenses.

N Lenses
N lenses use Nano Crystal Coating on the surface of the lens to reduce ghosting and flaring of the lens when facing directly into light.

PC
PC lenses are perspective correction lenses with tilt and shift facilities to correct for perspective distortion.

PC-E
PC lenses are perspective correction lenses with tilt and shift facilities to correct for perspective distortion. These lenses also provide an electronic diaphram to provide auto aperture controlwhen used with certain cameras. The cameras include the D3, D700 and D300.

VR Lenses
These lenses utilise Nikons Vibration Reduction (VR) technology to reduce camera shake movement and they give an effective gain of several stops in shutter speed at slower shutter speeds.

Nikon 60mm and 105mm AFS Micro Lens
If you are using these lenses you should understand that it has some special features as follows:

These lenses are normal focal length when focussed at infinity however when focussed close up, at a reproduction ratio of 1:1 the focal length of the lens shortens significantly.
These lenses also pass the effective aperture to the camera, not the actual aperture. When focussed at a reproduction ratio of 1:1, the effective aperture passed to the camera will be approximately f/4.8 for each of these lenses, not the actual apertures of f/2.8. When focussed between infinity and a reproduction ratio of 1:1 the effective aperture will be between f/2.8 and f/4.8.
These lenses are unsuitable for use with bellows such as th PB6 or Nikon extension tubes as they are G lenses and the bellows or extension tubes have no mechanical or electrical linkage for aperture control.

Nikon 200mm AF D Micro Lens
If you are using this lens you should understand that it has some special features as follows:
This lens is 200mm when focussed at infinity however when focussed close up at a reproduction ratio of 1:1, the focal length of the lens reduces to approximately 140mm.
The lens also passes the effective aperture to the camera not the actual aperture. When focussed at a reproduction ratio of 1:1 the effective aperture passed to the camera will be f/5.3 not the actual aperture of f/4. When focussed between infinity and a reproduction ratio of 1:1 the effective aperture will be between f/4 and f/5.3.