Nikon D7000 manual On/Off switch

84 David Busch’s Nikon D7000 Guide to Digital SLR Photography

■Aperture lock. If you want your D7000 (or other Nikon dSLR) to control the aper- ture electronically, you must set the lens to its smallest aperture (usually f/22 or f/32) and lock it with this control.

■Focus limit switch. Some lenses have this switch (shown in Figure 3.32), which limits the focus range of the lens, thus potentially reducing focus seeking when shooting distant subjects. The limiter stops the lens from trying to focus at closer distances (in this case, closer than 2.5 meters).

■Vibration reduction switch. Lenses with Nikon’s Vibration Reduction (VR) fea- ture include a switch for turning the stabilization feature on and off, and, in some cases, for changing from normal vibration reduction to a more aggressive “active” VR mode useful for, say, shooting from moving vehicles. More on VR and other lens topics in Chapter 11.

Vibration reduction	Focus limit	Normal/Active
On/Off switch	switch	VR mode switch

The back end of a lens intended for use on a Nikon camera has other components that you seldom see (except when you swap lenses), shown in Figure 3.33, but still should know about:

■Lens bayonet mount. This is the mounting mechanism that attaches to a match- ing mount on the camera. Although the lens bayonet is usually metal, some lower- priced lenses use a rugged plastic for this key component.

■Automatic diaphragm lever. This lever is moved by a matching lever in the cam- era to adjust the f/stop from wide open (which makes for the brightest view) to the taking aperture, which is the f/stop that will be used to take the picture. The actual

Figure 3.32

Some lenses have focus limit switches and controls for vibration reduction (VR) features.