Where can I find information on setting f stops and shutter speed on a 14 Pro

When you use the built in Camera app, then that app does not have an option to use Manual Mode whereby you can set your own Shutter Speed and Aperture. You can control the depth of field before or after the image is captured by choosing Portrait Mode and then adjusting the Aperture to control the DOF.

More information here 👉 Use Portrait mode on your iPhone - Apple Support

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Adjust Depth Control and Portrait Lighting

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

1. Tap a Portrait mode photo in your library.
2. Tap Edit, then tap the Depth Control button  at the top of the screen to adjust Depth Control or Portrait Lighting button  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.

Axel F.

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Where can I find information on setting f stops and shutter speed on a 14 Pro