Appearance
Calibrate the On-Screen Ruler
The Viewer displays a physical-scale ruler at the top of the screen so inspection measurements can be referenced directly against the card. For the ruler to be accurate, it must be calibrated once per device.
When to calibrate
Calibrate when:
- Setting up a new device for inspections
- The on-screen measurements appear to differ from a physical ruler
- You have changed the screen resolution or zoom settings
Calibration is stored per device and survives sign-outs.
How to calibrate
- Open the Settings tab (ruler icon in the tab bar).
- Scroll to Ruler Calibration.
- Hold a physical ruler flat against the screen, aligned to the left edge.
- Use the − and + buttons to adjust until the blue bar measures exactly 10 cm from the left edge.
- The current value is shown as N px / cm.
- Tap Save calibration when the bar matches your ruler.
📸 Screenshot — Ruler Calibration section in Settings
The Ruler Calibration section of the Settings screen, showing the blue calibration bar, the − value + stepper controls, and the "Save calibration" button below. Ideally capture this with a physical ruler held against the screen to show the calibration process in action.
A "Calibration saved ✓" message confirms the setting was stored.
Tips
- Use the same ruler you'll use in the field to minimise parallax error.
- Calibrate with the device brightness at its normal working level.
- The calibration is device-specific. If multiple technicians share a device, calibration only needs to be done once for that device.