how to adjust depth of field on 1phone 12 pro

Hello Daviddsmp,

We see you're wanting to adjust the the depth-of-field on your iPhone 12 Pro. We'd be happy to provide information.

The feature is an effect that is created with Portrait mode. This effect lets you compose a photo that keeps your subject sharp while blurring the background. This is an automatic feature.

After you take a photo in Portrait mode, you can adjust the level of background blur and the intensity of Portrait Lighting effects. Here's how:

1. Tap a Portrait mode photo in your library.
2. Tap Edit, then tap the Depth Control button at the top of the screen (the button looks like an "f" inside of a circle) to adjust Depth Control or Portrait Lighting button (this button will have a bold circle inside another circle inside of a hexagon) to adjust Portrait Lighting. A slider appears below the photo.
3. Drag the slider left or right to adjust the effect. A gray dot above the slider marks the original value for the photo.
4. Tap Done.

You can learn more about this feature and how to use it here: Take Portrait mode photos with your iPhone camera.

Thanks for using Apple Support Communities. Have a good one!