Advantages of photogrammetry in data gathering
As it is the case for many technologies, photogrammetry also reduces the field time for technicians to collect data. By saving time, you save money and are given the certainty that the gathered information is accurate.
Photogrametry is a technique which spans time. Old aerial photographs may be used as reference many years later.
Examples of surveys using photogrametry
Mapping (eg : flood plains)
With the precise data collected through photogrammetry, land surveyors can recreate maps identifying flooding areas on the site for municipalities or MRC, for instance.
Evidence in an expert report
You want to prove that a fence has been an existing structure for over 30 years? You need evidence that a road was moved 40 years ago? Through photogrammetry, it is possible by referring to old time photographs. Such archival records are useful and solid proofs in an expert report.