Certified Photogrammetrist Study Guide 2026

Radar layover occurs when tall objects appear to lean toward the sensor due to the near-range compression of elevated objects; the photogrammetric analogue is relief displacement, where objects appear displaced from their true position.

Goniometer calibration uses a precision instrument with collimators to project parallel rays simulating targets at infinity, enabling measurement of angular relationships and lens distortion in a controlled lab environment.

Image classification is the process of categorizing pixels in a remotely sensed image into different land cover or land use classes (e.g., forest, water, urban, agriculture). This is achieved by analyzing the spectral characteristics of pixels and assigning them to predefined categories, creating thematic maps that represent the distribution of various features on the Earth's surface.

Point cloud thinning/decimation reduces the number of points by removing redundant ones while preserving the essential shape and detail of the surface, making processing more manageable.

USGS NMAS requires that 90% of well-defined points on a 1:24,000-scale map be within ±40 feet (±12.2 meters) of their true position.

The primary purpose of land surveying is to accurately determine and map the terrestrial or three-dimensional position of points, and the distances and angles between them. This is essential for establishing and defining property boundaries, planning and designing infrastructure, and creating precise maps for legal, engineering, and construction purposes.