Calibrating the M3T Thermal Camera in the DJI Pilot App

Step-by-Step: Calibrating the M3T Thermal Camera in the DJI Pilot App

1. Ensure Proper Setup

• 1. Power On the Drone and Remote Controller

     • Ensure the M3T drone and remote controller are powered on and connected.

     • Open the DJI Pilot app on the remote controller.

  2. Access the Camera Settings

     • Tap on the Camera Settings icon in the DJI Pilot app.

     • Select the Thermal Camera tab.

  3. Start the Calibration Process

     • Locate the Flat-Field Calibration (FFC) / NUC (Non-Uniformity Correction) option.

     • Tap Calibrate to begin the process.

  4. Wait for Calibration to Complete

     • The camera will automatically adjust for optimal thermal image quality.

     • Avoid moving the drone during the calibration process.

  5. Verify the Calibration

     • After calibration, check the thermal feed for any inconsistencies.

     • If needed, perform additional calibrations for improved accuracy.

2. Temperature Calibration (Emissivity Settings)

While DJI Pilot doesn’t require manual calibration for basic temperature readings, it’s important to adjust the emissivity for accurate thermal data, particularly when inspecting different materials:

• In the Camera Settings menu, look for the Thermal Settings option (usually under the settings tab labeled as “Thermal” or similar).
• Adjust the Emissivity value based on the materials you are inspecting. The default emissivity for most materials is set to 0.95, but you may need to adjust it for specific roof materials like metal, asphalt, or concrete. For instance:
  • Concrete/Asphalt: 0.95
  • Metal: 0.85 to 0.90
  • Wood: 0.90 to 0.95
• Please use the correct emissivity value for accurate temperature readings, especially if you look at different surfaces.
  
  

3. Automatic Thermal Calibration

The DJI Mavic 3 Thermal drone is designed to perform automatic thermal calibration when you first power on the camera and during flight. However, it’s important to understand how the camera operates in different temperature conditions:

• If the temperature difference between the roof or inspected area and the surrounding environment is too small, you may need to adjust the temperature range manually to highlight the anomalies.
  
  
• Manual Temperature Range Adjustments:
  • You can adjust the temperature range for more precise readings in the Thermal Settings tab.
  • Set the lower and upper bounds to better capture roof temperature variations, especially in the case of minor discrepancies like insulation issues.
    
    

4. Thermal Image Calibration (Manual Adjustments)

• Palette Selection: Choose an appropriate color palette that clearly highlights temperature differences. Ironbow or High-Contrast palettes are ideal for roof inspections.
• Temperature Span: You can set the temperature span to adjust the thermal image contrast automatically, which helps differentiate heat from cold spots. This is not strictly a calibration but helps enhance thermal readings.
  
  

5. Thermal Image Optimization

• If the thermal image is too bright or dark, you can adjust the contrast in the settings to optimize image visibility.
• During calibration, ensure that the thermal sensor is not too exposed to direct sunlight, as extreme sunlight exposure can distort the camera’s readings.
  
  

6. Perform the Calibration Check

• After adjusting focus, emissivity, and temperature settings, check the thermal image on your screen.
• Hover over a known temperature reference (e.g., a shaded spot on the roof or a specific material with a known temperature) to verify the accuracy of the readings.
• If the readings are consistent with the actual temperature of the reference object, the camera is calibrated correctly.
  
  

Additional Tips for Calibration and Thermal Settings

• Temperature Consistency: If there are significant temperature differences between the roof and the surrounding environment, the camera may take a few moments to stabilize and display consistent thermal images. Allow time for the camera to adjust if needed.
• Warm-Up Period: After powering up the drone, let the thermal camera warm up for a few minutes to ensure it is properly calibrated and ready for accurate readings.
• Environmental Conditions: Always monitor the ambient temperature. Significant temperature changes can affect thermal readings, so inspections should be conducted in inconsistent ecological conditions for the best results.
  
  

Summary

The DJI Mavic 3 Thermal does most of the thermal camera calibration automatically, but you can improve accuracy by:

• Adjusting the manual focus for sharp images.
• Setting the correct emissivity for the material being inspected.
• Fine-tuning the temperature range and color palette for better visibility of thermal anomalies.
• Allowing the camera time to warm up and adjust to environmental conditions before starting your inspection.
  
  

Following these steps ensures that you’ll get the best possible thermal imagery for your roof inspections with the DJI Mavic 3 Thermal.