The camera

The exact iPhone settings — for the gray-card method specifically.

You almost certainly do not need this chapter. Every session started today is directed by your phone, which sets its own camera — nothing here has to be switched on by hand. This is kept for readings captured the older way, by shooting ProRAW yourself and moving the files to a computer.

• Settings → Camera → Formats → ProRAW & Resolution Control: ON. Pro Default: ProRAW 12 MP. why: 12 MP bins four pixels into one: cleaner color and less noise than 48 MP. Color sampling needs signal quality, not resolution. Files are ~25 MB instead of ~75
• In the Camera app, tap the RAW badge so it is NOT struck through. why: the toggle resets. Check it every session
• Photographic Styles: Standard / off. No filters, no edits after. why: styles deliberately re-tone skin; an edited photo also shares as JPEG, destroying the RAW
• REAR camera, propped at eye level ~4 ft away, self-timer 3–10 s. why: the selfie camera is tuned to flatter, not to measure. With RAW active the timer takes a single frame instead of a burst
• Long-press your cheek in the preview until AE/AF LOCK appears, then drag the sun slider slightly DOWN (~⅓ stop). why: otherwise the camera meters the bright window and guesses; RAW recovers underexposed shadows easily but blown highlights are gone forever