How do I start photogrammetry?

Photogrammetry is the process of creating 3D models or measurements from 2D images. Here's a basic guide to help you get started with photogrammetry:

1. Understand the Basics:

• Photogrammetry Types:

  • Close-range Photogrammetry: Typically used for small objects.
  • Aerial Photogrammetry: Involves capturing images from an elevated position, often using drones or aircraft.

• Key Concepts:

  • Feature Points: Distinct points in an image used for matching.
  • Overlap: Images should overlap to ensure proper coverage.
  • Camera Calibration: Understanding and correcting lens distortions.

2. Equip Yourself:

• Camera:

  • Use a good quality camera. Higher resolution cameras generally yield better results.
  • Ensure proper settings (manual mode, fixed focus, white balance).

• Software:

  • Choose a photogrammetry software. Popular choices include:
    • Agisoft Metashape
    • RealityCapture
    • MicMac
    • Meshroom (open-source)

3. Capture Images:

• Plan your Shoot:

  • Consider the subject and its features.
  • Plan the shooting locations and camera positions.
  • Ensure proper lighting conditions.

• Take Overlapping Photos:

  • Ensure significant overlap (60-80%).
  • Use a consistent angle and distance between shots.

• Camera Settings:

  • Manual mode for consistent exposure.
  • Fixed focus.
  • Use a tripod to avoid camera movement.

4. Processing:

• Import Images:

  • Load your images into the photogrammetry software.

• Camera Calibration:

  • If required, calibrate your camera within the software.

• Point Cloud Generation:

  • The software will identify common points in images and create a point cloud.

• Mesh Generation:

  • The point cloud is used to create a 3D mesh.

• Texture Mapping:

  • Apply textures to the mesh for realistic appearance.

5. Refinement and Export:

• Refinement:

  • Fine-tune the model as needed.
  • Address any issues with geometry or textures.

• Export:

  • Export your 3D model in a suitable format (e.g., OBJ, FBX).

6. Practice and Learn:

• Experiment with Different Settings:

  • Adjust camera settings and software parameters to see how they affect results.

• Learn from Mistakes:

  • Analyze failed attempts to understand what went wrong.

• Community and Resources:

  • Join photogrammetry forums and communities for advice and support.

7. Continue Improving:

• Advanced Techniques:

  • Explore advanced photogrammetry techniques.
  • Experiment with more complex scenes and subjects.

• Stay Updated:

  • Photogrammetry software and techniques evolve. Stay informed about updates and improvements.

8. Optional: Aerial Photogrammetry:

• Drone Usage:

  • If you're interested in aerial photogrammetry, learn to use drones for capturing images.

• Regulations:

  • Familiarize yourself with local regulations regarding drone usage.

Remember, photogrammetry is a skill that improves with practice. Start with simple objects and scenes, and gradually progress to more complex projects as you become more comfortable with the process.