There is not much difference, but a motor is added in the second generation, which solves the problem that Nikon D5000, 3000, 60 and 40 can't focus automatically. So the second generation can be used in Nikon, which has no body motor. If it is a machine above D70, there is no need to buy the second generation, because the focusing speed of Longteng's motor is sometimes not as good as that of the fuselage motor. & gt