Accuracy Articles

Three vehicles of varying size were measured using an optimized, practical photogrammetry technique and the results were
compared to measurements acquired via total station and a FaroArm. This research shows photogrammetry can be highly
accurate and efficient with proper methodology, while also expanding on the photogrammetry literature database and improving confidence in the technique.

The article shows that PhotoModeler Scanner can match (if not exceed) the accuracy of a laser scanner. This article also demonstrates the optimal way to set up photogrammetry projects to maximize DSM accuracy.

Many application specialists may find portable device (smartphone, tablet) cameras an attractive proposition where some modest photogrammetric capability would be useful. This paper investigates the geometric potential of these cameras for close range photogrammetric applications.

The aim of this work is the establishment of an efficient and accurate digital camera calibration method to be used in particular working conditions, as it can be found with our UAV (Unmanned Aerial Vehicle) photogrammetric projects.

Engineering deformation monitoring requires techniques which can produce high precision and accuracy, reliable measurements at good temporal resolution and fast processing speed. Moreover, monitoring in civil engineering is generally considered to be labour-intensive and financially expensive, and it can take significant effort to arrange the necessary human resources, transportation and equipment maintenance. Such requirements are especially true for monitoring non-rigid membrane structures (defined in this paper as covers or enclosures in which a fabric surface is pre-shaped and pre-tensioned to provide a shape that is stable under environmental loads). Low cost, automated, photogrammetric techniques therefore have the potential to become routinely viable for the structural monitoring of non-rigid membrane structures in the future. This research is investigating the use of close range photogrammetry to be applied at all stages of membrane structure engineering, from materials testing, through dimensional control in construction to in-situ, as-built monitoring of the finished construct.

What is unique in this study is that accuracy was assessed on a system with four independent cameras and all those cameras were consumer-grade cameras with zoom lenses. This is a configuration one might use for a low-cost PMV system (for tracking object movement and shape change over time).

We conducted an experiment to determine PhotoModelers precision using commonly available and reasonably priced equipment. We demonstrate that any customer can achieve very high precision with PhotoModeler Pro 5. In addition we discuss two common terms, Precision and Accuracy, and why they are important to understand.

Mike Fedak performed a study to investigate the accuracy of a measurement system using PhotoModeler Pro, a consumer-grade digital camera, and retro-reflective targets.

NASA’s Gossamer Spacecraft Initiative has been evaluating optical structural testing and validation, with the leading candidate technology being photogrammetry. This paper discusses photogrammetric measurements of a 5m-diameter inflatable space antenna using four Kodak DC290 (2.1 megapixel) digital cameras. The study had two objectives: to determine the photogrammetric measurement precision obtained using multiple consumer-grade digital cameras, and to gain experience with new commercial photogrammetry software packages, specifically PhotoModeler Pro from Eos Systems, Inc.

Dr. Hanke did a sample architectural-like measurement project with two different cameras a 35mm film camera scanned on a flatbed office scanner and a medium format metric camera scanned with Pro-PhotoCD.