Lumiz FZ1000 - what's the point of the AF/AE lock button?

[wobbly bob]

I must be missing something here, but what is the point of the lock button? I can achieve the same results by pointing the camera at the subject, half pressing the shutter and as I continue to hold it, reframing the picture.
I know the lock button can be set for just AF, AE etc. as required, but don't get why I would want both when half pressing the shutter button does the same thing. Surely I'm failing to understand something here!

 

[Mike Drone]

So that you can take multiple photos with the same ISO, Aperture, and Focus (Depth of field) without readjusting the camera in a photo set. Sometimes I use the timer to take the photo to limit the amount of touching of the camera for shake, etc..

 

[weepete]

It's to seperate your exposure settings from the shutter click. Metering often happens in the centre of the frame (for CWA, spot, and partial metering). Particularly with spot metering it would enable you to meter off a tone in the scene and recompose. Similar to focus, recompose.....but with metering.

eg to hold the whites in clouds, you could meter on them, add some -EC, hit exposure lock, compse, and fire the shutter in the semi automatic modes.

 

[wobbly bob]

Thanks to you both.