Everyday setup, custom buttons, the ISO sweet spots, and phone remote control
| Button | Assigned |
|---|---|
| C1 | Creative Styles |
| C2 | Focus Area |
| C3 | Focus Mode |
| C4 | Monitor Brightness |
Both bodies quietly switch to a cleaner high-gain mode at a set ISO. Below that, ISO 100 gives maximum dynamic range; at the switch point, read noise drops and shadows lift more cleanly — so it's often better to jump straight there than to sit at an intermediate value.
| Camera | Base ISO | Gain switch | Remember |
|---|---|---|---|
| a7R III | 100 | ~ISO 640 | think 100 → 640 |
| a6400 | 100 | ~ISO 400 | think 100 → 400 |
The a6400's native range is 100–32000 (above that is extended/software-boosted). The switch applies to RAW stills; JPEG/video get extra processing.
On NFC bodies, tap the phone to the NFC logo to launch and connect automatically; otherwise start Smart Remote from the camera's App menu and connect the phone to its Wi-Fi. You see a live view and can fire the shutter and adjust exposure compensation; the in-camera app update unlocks full aperture/shutter/ISO control and tap-to-move AF.
Consolidated from notes: Setup Tips a6300; Settings for different modes a6300; Sony a7 Riii CUSTOM BUTTONS; Native ISO range of the Sony a6400; Dual gain mode ISO 640; Smart Remote app
Sourced from Claude