Which camera type is the simplest and commonly used for mapping photographs?

• A. Multi-lens camera
• B. Orthographic projection
• C. Single-lens camera
• D. Isoplets

Answer: (C)

When mapping photographs, the key is a simple, well-defined way to project the 3D world onto a 2D image so measurements can be derived accurately. A single-lens camera uses one optical center, yielding a single perspective projection. This makes the relationship between image coordinates and real-world coordinates easy to model, calibrate, and solve for position and orientation, which is essential for reliable mapping and georeferencing. Because of its straightforward geometry, it’s the most practical and widely used choice in mapping.

A multi-lens camera adds complexity with multiple viewpoints and baselines, making calibration and the math of reconstruction much harder. Orthographic projection describes a parallel projection rather than how a camera actually images the scene, so it’s not the typical imaging model for mapping. Isoplets aren’t a camera type, so they don’t describe the imaging device used for mapping photographs.