diff --git a/topics/02_passive/index.md b/topics/02_passive/index.md index 40f2e4fd93129f1e58c4d8e3dafd7fe365b27852..fe3d8114ffed29369532df2031b953116d598c50 100644 --- a/topics/02_passive/index.md +++ b/topics/02_passive/index.md @@ -22,12 +22,16 @@ Photogrammetry was first documented by the Prussian architect [Albrecht Meydenba <img src="images/data_model_photogrammetry.png" alt="Data Model of Photogrammetry"> -A typical medium resolution aerial photogrammetry scan of a barn. With 50-100 images a reasonably accurate model can be produced. Such models are often used in surveying and restoration projects from the scale of hand helf objects to cities. +## Accessibility Photogrammetry offers remarkable accessibility and affordability. Unlike other scanning methods that require precise orbital plans or specialized equipment, photogrammetry can be achieved simply by flying a drone in a circular pattern and capturing multiple photos. Utilizing the location data from the drone, one can construct detailed models like the example shown here. This accessibility makes photogrammetry an attractive option for various applications, with results that can be sufficiently accurate depending on the specific requirements. <img src="images/house_scanning.jpg" alt="House"> +A typical medium resolution aerial photogrammetry scan of a barn. +With 50-100 images a reasonably accurate model can be produced. Such models are often used in surveying and restoration projects from the scale of hand helf objects to cities. + +## Markers However, it's essential to note that photogrammetry lacks inherent scale. Without a reference point or prior knowledge of the camera locations, the resulting model lacks a definitive scale, as cameras inherently lack absolute scale information. Therefore, incorporating at least one reference point is crucial. For example, marking a facade with visual markers or known distances, such as pieces of tape, allows for scaling within a 3D modeling program based on these references. # Stereo Matching