Manual exposure with auto ISO is the most practical exposure mode that most photographers leave unused. The RF 35mm f/1.8 IS Macro STM — Canon’s modest, versatile nifty-enough-fifty-equivalent for the R system — is the lens where this mode earns its keep, because the lens covers such a wide range of use cases in a single shooting session that fixed manual settings cannot follow it. The setup: set the camera to M mode, ISO to Auto, aperture to whatever the scene requires (f/4 for general use with context in the background, f/1.