Which is the simplest type of lens used for mapping?

• A. Single Lens
• B. Lens
• C. Multi-Lens
• D. Rutter

Answer: (A)

In mapping, using a single-lens camera keeps the projection geometry simple. With one lens, there’s a single projection center and a single focal length to model, which makes interior orientation (calibrating the camera itself) and exterior orientation (position and orientation in space) easier to solve. Fewer optical parameters mean you can correct distortion with a straightforward, well-understood set of adjustments and maintain a consistent scale across the image, which is crucial for accurate map products like orthophotos and 3D reconstructions.

When multiple lenses are used, each lens adds its own projection center and distortion characteristics, so the calibration and bundle adjustment become more complex. Aligning and integrating data from several lenses introduces additional potential sources of error and requires more intensive processing.

The other term isn’t a standard mapping lens type, so it doesn’t provide the same straightforward, single-path optical setup that makes a single lens the simplest choice for map production.