Anyone can buy a drone and photogrammetry software. Producing a surface that meets a stated accuracy, and proving it, is a different skill. The American Society for Photogrammetry and Remote Sensing (ASPRS) Certified Photogrammetrist credential is one of the few independent signals that the person responsible for your mapping has that skill. Here is what the credential requires, what the current ASPRS accuracy standards say, and what to ask for in your next scope.
What it takes to become an ASPRS Certified Photogrammetrist
ASPRS runs a peer-reviewed certification program. According to the ASPRS Certification Manual, a Certified Photogrammetrist candidate must have:
- Six years of experience in photogrammetry, at least three of them in a position of professional responsibility. A degree in engineering or the natural or physical sciences can count for a limited portion of that experience.
- Four references from people who hold or have held responsible photogrammetric positions and know the candidate's work firsthand.
- A signed declaration to follow the ASPRS Code of Ethics.
- A passing score on a written examination.
Certification lasts five years. To recertify, the photogrammetrist documents 100 professional development hours earned over the prior five years, across categories such as continued practice, training, conferences and service to the profession, and submits fresh references. Certification can be revoked for ethics violations or malpractice.
ASPRS also offers Certified Mapping Scientist credentials (remote sensing, lidar and UAS) and technologist-level certifications. The Certified Photogrammetrist is the senior credential specific to photogrammetric mapping.
What certification is and is not
ASPRS certification speaks to specialized photogrammetric expertise. Confirm licensing requirements for your project with your surveyor of record.
The ASPRS accuracy standards in plain terms
The ASPRS Positional Accuracy Standards for Digital Geospatial Data are the reference most public agencies and engineers use to specify and verify mapping accuracy. Edition 2 was approved in 2023 and Edition 2, Version 2 in 2024. Key points for engineers writing or reviewing a scope:
Accuracy is expressed as RMSE
Horizontal accuracy is stated as RMSEH (the combined radial error from X and Y), vertical as RMSEV, and Edition 2 adds a three-dimensional measure. Edition 2 dropped reporting at the 95 percent confidence level, so specifications should state RMSE values directly. Accuracy classes are open-ended: you specify the RMSE you need rather than picking from a fixed table of map scales.
Vertical accuracy in vegetation is reported, not pass/fail
Non-vegetated vertical accuracy (NVA) determines whether a product passes. Vegetated vertical accuracy (VVA) is tested and reported as found. This is a practical acknowledgment that ground under vegetation is harder to measure, and it is one more reason to plan supplemental field work in brushy terrain.
Ground control and checkpoints have defined accuracy requirements
Edition 2 calls for ground control, and for the checkpoints used to test the product, to be at least twice as accurate as the target product accuracy. Earlier guidance was stricter on paper (four times for control and three times for checkpoints), but Edition 2 now factors the checkpoint survey's own error into the final accuracy computation, which is more honest at high accuracy levels.
Testing needs enough checkpoints
The minimum is 30 checkpoints for typical project areas, increasing for very large areas up to a cap of 120. Checkpoints should be independent of the control used to build the product and spread across the site. Very small projects where 30 checkpoints are not practical are addressed separately in the standard.
Addenda cover photogrammetry and UAS best practices
Version 2 added best-practice addenda, including photogrammetry, lidar, UAS and oblique imagery, alongside general guidelines and field surveying of control and checkpoints.
Why this matters on your project
A certified photogrammetrist working to these standards brings practical value:
- Accuracy specified up front. The scope states RMSEH and RMSEV targets tied to your design needs, not a vague "survey grade."
- Control designed for the target. Control density, distribution and survey method are chosen to support the stated accuracy.
- Independent testing. Checkpoints are kept out of the adjustment and used only to test the result.
- A clear accuracy statement. The deliverable reports tested accuracy in the language of the standard so reviewers and agencies can rely on it.
- Known limitations disclosed. Vegetated and obscured areas are identified and handled with supplemental methods instead of being smoothed over.
Questions to ask any mapping provider
- Who is the responsible photogrammetrist, and what are their credentials?
- What RMSEH and RMSEV will you deliver, and how many independent checkpoints will you use?
- What datum, projection and units will the deliverables use?
- How will vegetated or obscured areas be handled and reported?
FAQ
Is an ASPRS Certified Photogrammetrist the same as a licensed land surveyor?
ASPRS certification is a national professional credential for photogrammetric expertise. Confirm licensing requirements for your project with your surveyor of record.
What accuracy standard should I put in my scope?
Reference the current ASPRS Positional Accuracy Standards for Digital Geospatial Data and state the RMSEH and RMSEV values your design needs, plus the number of checkpoints for testing.
How often must ASPRS certification be renewed?
Every five years, with documented professional development hours and new references.
Get accuracy you can document
Arrowhead Mapping has 30 years of mapping experience in Southern California, directed by Steve Dillon, ASPRS Certified Photogrammetrist #790. Call (909) 889-2420 or reach us at /contact to discuss your accuracy requirements.