iPhone 8 - how do I maximize resolution?

Looking at my 6th gen iPad just now, there is no method to choose an image size.

High Efficiency or Most Compatible has nothing to do with pixel dimensions. That's just a choice between using the newer HEIF/HVEC compression formats, or the standard JPEG/H.264. The first of each is for still images, and the second for video.

Not having an iPhone 8 to look at, I don't know if there are further choices to choose an actual image size.

That is not adjustable if you want to keep all of your features. If you go to settings>camera>formats you can choose High efficiency or most compatible.

Thanks. I was thinking that because HE reduces the file size it is also reducing the resolution.

Nope, it's just a compression difference.

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