When you hear your new lens rattle for the first time, it's a terrifying thought. Let's face it, you probably spent a lot of money on new equipment, and you're not going to be impressed if it breaks down right away. Rather than calling the manufacturer's customer service line to complain, know that your rattling lens is normal.
It's typical for your lens to rattle or clunk. After stabilising the glass elements in the lens, the Image Stabilizer disengages from the optics, which you can hear. Apart from that, whatever other sound you hear when the lens is attached to the camera is most likely the autofocus or aperture.
Manufacturers aim to obtain optimal image quality while minimising camera shake, which leads to the development of an image stabiliser. Stabilization aids a static image on the sensor by accounting for movement within the lens. The components of an image stabiliser differ based on the motors, brand, and pricing of the lens. A stabilisation system's three major components are gyro sensors, a stabilisation lens element group, and a microcontroller.
When you half-press your camera's shutter button, all three parts work together to balance any hand-held or vehicle movement. The gyro sensors send data to a computer, which sends instructions to a collection of specialised parts in the lens to counteract any movement.
All stabilisation calculations are performed in real time. The entire process is completed in a flash to ensure that your shutter speed is not affected by camera shake. It's crucial to keep in mind that no stabilisation solution is flawless, although technology is evolving to help photographers and filmmakers.
For example, in the case of sports or wildlife photographers, the gyro measuring yaw can be turned off. When the stabiliser is turned on, it solely compensates for pitch when capturing moving things. This setting prevents the viewfinder from panning. To engage the control, users just move a switch on their lens.
Many manufacturers set the mechanism to lock into a specific position. You may hear a rattle as the set of parts returns to their locked position after you release the shutter button. Alternatively, if you quickly remove an active stabilised lens from a body, the stabilisation elements will be audible motions that lock into the same position.
Taking care of your lens
Image Stabilized lenses should be stored in a proper case or bag compartment, according to the manufacturers. You don't want the lens moving around in a loose bag, so make sure you pack it with appropriate padding. The stabilised lens group will lock into a specific position when not in use. Some of the lens group elements in the lens may move slightly in a locked position during transportation. It's quite normal if this happens. Nothing horrible is going to happen.
You don't want to shake your lens too hard or too long to hear the rattling! You may have seen videos of individuals doing this on the internet; it is not recommended. The gyros, microprocessor, and group of components could all fail in rare cases, leading some stabiliser frequencies to malfunction. The gyros, for example, process commands to a microcontroller at 0.5Hz to 3Hz for hand-held stabilisation. Alternatively, the stabiliser processes data at a frequency of 10Hz to 20Hz to accommodate for vehicle motions.
Power down your camera to allow the stabilised lens elements to return to their fixed position, which will stop some older stabilised systems from rattling. If you remove the lens when stabilisation is engaged, you'll almost certainly hear a rattling because the lens isn't secured in place. To solve this, return the lens to its original position and turn off the camera. The lens group elements will lock together, and the rattle will be gone.
You may hear a humming noise, which is often a dull-sounding 'robot-like-hum,' if you have automatic focus turned on. If this is the case, the linear motor is in charge of driving the lens' autofocus. You may check this by switching the lens to manual focus. The hum will go away as soon as you make this change. When you hear this noise across all brands, there's nothing wrong with the lens. Turning the focus to manual is recommended if you're filming a video and want to avoid noise.
Manufacturers have improved the internal noises connected with autofocusing over time. Many earlier lenses included cutting-edge technology at the time, but technologies have subsequently developed to provide better focus mechanisms.
Canon autofocus system noise
Ultra Silent Motors (USM) and Stepping Motors are the two main focus technologies used by Canon (STM). The latter is their most recent innovation, and it is quieter than USM lenses. The somewhat louder noise you'll hear with USM technology is caused by the lens's glass moving; the motor itself is ultrasonic and therefore inaudible to humans. If your lens is ancient, it may not even have USM or STM; in this scenario, your lens will be the loudest because the autofocus system will be driven by a micromotor.
Nikon autofocus system noise
Back in the day, Nikon used an autofocus system with an integrated focus motor (AF-I). Internal Focusing (IF) and Silent Wave Motor are examples of advances in lens technology (SWM). Because the glass in the lens moves, these autofocus systems, like Canon's, are loud. In some situations, if you don't clean your lens with a filter, debris or sand might get into the lens, making the noise considerably louder. If this is the case, contact the manufacturer to arrange for a lens repair.