Multi-device monitoring and mirroring

[erik-sutton95]

Goal

Allow an iPhone connected to and mounted on the camera to act as the primary OpenZCine monitor and securely share its live feed with additional iPhones, iPads, and Android devices for other crew members on set.

Why it matters

The camera operator needs a low-latency main feed with full monitoring and camera controls, while directors, focus pullers, clients, and other crew may also need to see the shot. Giving each person a secondary monitor would make OpenZCine more useful for collaborative shoots without giving every viewer unrestricted access to the camera.

Proposed experience

• The camera-connected iPhone acts as the host and remains the authoritative camera-control device.
• Nearby iPhones, iPads, and Android devices can join the host session and view the live feed.
• Secondary devices can use appropriate monitoring tools such as frame guides, false color, zebras, focus peaking, scopes, and LUT preview.
• The host can choose whether monitoring-tool settings are synchronized or configured independently on each viewer.
• The host can assign permissions or a role to each connected device.
• A view-only role cannot start or stop recording or change camera settings.
• More trusted roles can optionally receive selected controls, such as record control, while exposure, focus, media, and other settings remain locked.
• The host can review connected devices, change permissions, revoke access, or disconnect a viewer at any time.
• Joining should be quick on set, with clear session identity and protection against unauthorized viewers.
• Each device should show connection quality and feed delay clearly enough to avoid mistaking a delayed image for the camera's current state.

Success looks like

An operator can mount one iPhone on a Nikon Z camera, use it as the primary OpenZCine monitor, and share a responsive feed with several crew devices. Each viewer gets the monitoring tools they need, while the operator retains explicit control over who can record or change camera settings.

Open questions

• Which local transport provides acceptable latency, image quality, reliability, and cross-platform support?
• Should monitoring overlays be rendered independently on each device, synchronized from the host, or optionally baked into the shared feed?
• How many viewers can a primary phone support without excessive heat, battery drain, or reduced camera-monitoring performance?
• Should sessions work over an existing local network, a hotspot hosted by one device, or both?
• Which roles and individual control permissions are needed for common crew workflows?
• How should discovery, pairing, encryption, reconnection, and access revocation work on set?
• What limitations will apply to Android viewers during the initial Android rollout?

[erik-sutton95]

Additional use case: mirror playback/review to viewers

An operator uses an iPhone tethered to a Nikon ZR as the primary monitor and broadcasts live view to an iPad held by a client. When the operator enters playback to review footage, the primary phone can show it but the viewer's feed stops.

Please extend the mirroring scope to include an explicit review/playback state: authorized viewers should receive the currently selected still or video, including scrub/play state where feasible, while camera control remains with the host. The host should be able to choose whether playback is shared, and secondary devices must clearly indicate that they are reviewing recorded media rather than a live feed. This would let operator and client review takes together without handing over the primary device.