What's the difference between "D" and "G" behind the SLR lens?

The unique symbol of Nikon lens, D head has no lens motor and needs a camera with body motor to drive autofocus. ? G-head has a lens motor, and Nikon cameras can drive autofocus.

Nikon, a famous Japanese camera manufacturer, was founded in 19 17, formerly known as Japan Optical Industry Co., Ltd.. 1988 Company changed its name to Nikon Co., Ltd. based on its camera brand.

Simply put, one is a manual head (D head) and the other is an automatic head (G head) with its own motor. D-head has no lens motor (SWM, I forgot the details, it seems to be a silent wave motor). On some low-end machines without body motor, such as D3 100 and D5 100, we can only rely on manual focusing and manual aperture conversion. On the other hand, D-head can complete autofocus and fuselage aperture change (that is, lock the aperture ring on the lens and change the aperture on the fuselage) on the machine with the fuselage motor above D7000.

G-head saves all these troublesome procedures, and comes with a focus motor, so that both high-end and low-end machines can complete the operation of fuselage aperture conversion. Compared with the D-head, especially on the low-end machine, the operation is simpler and clearer.

Moreover, according to Nikon's official statement, all G-heads, that is, relatively new lenses, are optimized according to the digital SLR body. That is to say, the performance of G-head in digital SLR is better than that of D-head (of course, this statement is based on Nikon official website's statement, and the actual situation is another matter).