My Tamron 24-70 F2.8 G2, used with Nikon D750, is making clicking sounds when I change the aperture in live view mode on M or A setting. Is the clicking normal?
DSLRs have two modes to operate them:
- The classic viewfinder-approach: You set the aperture, shutter speed, and ISO value. The only ways to know if you exposed properly is either the exposure meter - or to take a picture and find out by looking at the result. It is possible to preview the change in depth of field with most cameras as they offer a depth-of-field preview button that will tell the lens to close the aperture to the value you set.
- The LiveView-approach (used by MILCs per default): What you see is what you get. To do that, the camera tries to change all parameters live.
And this is why you hear a clicking sound - it sets the aperture as soon as you change it.
Yes, it is normal.
When using the optical viewfinder, the lens always remains wide open until the moment the photo is taken. The sound of the electronic aperture closing at the moment of exposure is masked by the sound of the shutter or mirror operation.
When using LiveView(depends on camera or features enabled) or Video mode, you will hear the aperture blades snap into position as you change the aperture setting.
Some lenses are louder than others, but they all make some kind of noise.
With some cameras, if you turn off "Exposure Preview" or "Exposure Simulation", the clicking noise might stop.