This article covers two types of 'Nikon SWM' motors.
All Nikon Lenses type Nikon AF-S use the built-in Nikon SWM (Silent Wave Motor) focusing motor.
There are two main types of Nikon SWM technology.:
- Nikon SWM ring motors (in Western literature they may be called Ring SWM)
- SWM based on gear motors (may be called 'Micromotor SWM' or 'Gear SWM' or 'Compact SWM' in Western literature).
In both cases, the idea of turning the waves into rotational motion is used, which allows you to move the lens of the lens (to focus).
Ring motors Nikon SWM (Ring SWM)
Ring motors are quite expensive, they have a construction without extra gears, they look like several metal rings. Such motors can very quickly, quietly and accurately move the lens of the lens. They look like this (taken from here):
Lens motor Nikon ED AF-S VR-Nikkor 70-200mm 1: 2.8G Vibration Reduction SWM IF (MKV, VRI), Nikon AF-S Nikkor 17-55mm 1: 2.8G ED IF SWM DX, Nikon N AF-S Micro Nikkor 105mm 1: 2.8G ED VR SWM IF Micro 1: 1 Nano Crystal Coat (now it’s clear why the macaroons are so chubby):
Motor for Nikon AF-S Nikkor 18-70mm 1: 3.5-4.5G ED DX SWM IF Aspherical (now it is clear why the 'simple' 18-70 / 3.5-4.5 focuses as quickly as TBU) and Nikon DX AF-S Nikkor 12-24mm 1: 4G ED SWM IF Aspherical (Now it’s clear where the price tag for this lens comes from):
Motor for Nikon ED AF-S Nikkor 17-35mm 1: 2.8D SWM IF Aspherical, Nikon ED SWM AF-S Nikkor 28-70mm 1: 2.8D, Nikon ED AF-S Nikkor 300mm 1: 4D IF Silent Wave Motor (now it is clear where the same problems with 'focus whistle' for these models come from):
Motors for Nikon AF-S 200mm F / 2, 300mm F / 2.8, 400mm F / 2.8, 500mm F / 4, 600mm F / 4, 200-400mm F / 4:
Motor for not very successful Nikon ED AF-S Nikkor 24-120mm 1: 3.5-5.6G SWM VR IF Aspherical:
Nikon SWM gear motors
These motors were created to reduce the cost of production. They generate slightly more noise than 'real' ring motors. Outwardly, they look like ordinary micro-motors.
Motor for Nikon DX 18-55mm F / 3.5-5.6, DX 55-200mm F / 4.5-5.6
The difference between ring and compact SWM motors is visible to the naked eye.
From my own experience I will say that lenses with ring motors have really better performance during focusing.
And now the sad truth. Some Nikon TOP lenses use SWM babies instead of a ring SWM. It is known with certainty that the Nikon 85 / 1.4G and Nikon 105 / 1.4E (exactly) uses compact SWM. I didn’t really believe that $ 85 Nikon 1.4 / 1600G can use a motor similar to the one in the Nikon 18-55 / 3.5-5.6 casing. Now everything fell into place and the reason for the slow focusing of the Nikon 85 / 1.4G became clear.
At one time, I was lucky enough to talk with a lens repairman, and he confirmed that many expensive Nikon lenses have horrible compact SWM motors (including the one mentioned by Nikon 85 / 1.4G).
Due to the fact that there is no marking on the Nikon lenses indicating the type of SWM motor, it is difficult to know what the buyer pays money for. Marketers won again.
Thank you for attention. Arkady Shapoval.