How to tell if Optical Image Stabilization is actually working on my iPhone 6 Plus Today I started getting suspicious that Optical Image Stabilization is not working on my iPhone 6 Plus. These are the factors that led me to my suspicion:


While recording a video, if I shake the phone lightly, the shakiness is visible in the preview. However, when I play the after recording, most of the shakiness is gone.
This makes it look like stabilization is only being applied only once the video is done recording: Optical Image Stabilization (at least the way Apple describes it) is supposed to move the physical sensor to compensate for movement, so I believe that the preview shown while recording should also be stabilized.
Based on the previous assumption that the physical sensor should move, I think that said movement should be apparent by observing the rear-facing camera while the camera app is open and the phone is being shaken lightly. Unless the actual moving parts are not directly visible, I don't think they're moving in my phone. Besides this, the inner part of the camera (the lens you can see right behind the outer glass and the black plastic around it) looks like it's slightly offset downwards, because I can see a small gap right above it, between the plastic and the frame of the camera. The same gap is not visible below the plastic, so it looks like it isn't centered. I have never seen the camera move from that position.


Is there a way to be sure that Optical Image Stabilization is actually working? Do the things I described only happen on my device?
The optical image stabilization on the iPhone 6 Plus has to do with a tiny motor changing the lenses while the sensor is fixed to the body of the phone.

It only engages for still photos and due to the size of the motors and limited space inside the device, it will be almost impossible to hear the sound of it in operation.

The real test will be if your phone isn't capturing sharp still images that are well lit and have some contrast lines for the focus pixels to establish what the proper focus should be. I suppose you would need to mount an iPhone 6 and 6 Plus on the same physical mount and take the same picture (burst mode) or using something to trigger both shutters at the same time.

Also, you might try taking pictures from a moving car out the side window and see if you can detect any difference in the EXIF metadata between pictures taken while moving versus pictures taken when still. Apple encodes all sorts of details and I would start by looking at the Focus Mode field to see if OIS is indicated there.



That said, optical image stabilization on professional canon and nikon lenses costing $4000 and up isn't magic and just gets you one or two stops of exposure for a given shutter speed. The effects are not huge so you are gaining a slight boost in the amount of light that can be gathered and the shutter is allowed to stay "open" for longer than if the OIS were not helping to keep the image centered on the CCD.