Photogrammetry

Photogrammetry is the art of reconstructing digital 3D models using photos.
To reconstruct a 3D model of an object, photos are captured from different angles.

Tips for capturing photos

As a general rule in photography:
The better the illumination, the better the captured photo.
Avoid reflecting surfaces.
For photogrammetry, the scenery, the objects and the lights have to stand still.
Even slight movements of the objects cause distortions.
Move the camera to obtain photos from different angles.

COLMAP

Put all photos into a folder called images inside a named project folder:

PROJECT="my_photogrammetry_experiment"
mkdir -p "$PROJECT/images"
cp *.jpg "$PROJECT/images"

Optionally (but highly recommended), create image masks for each image.
Image masks tell colmap where to look for keypoints during feature extraction.
For an image images/0123.jpg, the corresponding mask has to be named masks/0123.jpg.png.
No features will be extracted in regions, where the mask is black (pixel value 0).

Execute the reconstruction:

colmap automatic_reconstructor \
  --workspace_path "$PROJECT" \
  --image_path "$PROJECT/images" \
  --mask_path "$PROJECT/masks"

The reconstructed point cloud is written to:

$PROJECT/dense/0/fused.ply

The reconstructed mesh is written to:

$PROJECT/dense/0/meshed-poisson.ply

MeshLab

File > Import Mesh...

Filters > Remeshing, Simplification and Reconstruction > Surface Reconstruction: Screened Poisson
Reconstruction Depth: 12

Blender

File > Import > Stanford PLY (.ply)

Sculpting
In the toolbar at the bottom: Smooth

External Links

CONTENT.html	source	2025-10-19	2.6 KB
install_photogrammetry_env.sh	source	2025-10-19	2.3 KB
install_photogrammetry_env.sh 2025-10-19 by Gernot Walzl This script installs software used for photogrammetry (COLMAP, MeshLab, Blender). It was tested on Debian 13.