Photogrammetry vs LiDAR conversations are not the most productive way to approach deciding which sensors makes the most sense for an organization. Surveying and mapping professionals who work with these tools on a daily basis understand that each has its strengths and limitations, which means it’s not about determining which is “best” in a general sense but instead, which is the “best fit” for a given project or workflow.
Technology innovations with drones has made LiDAR data and imagery attainable, which has introduced an entire new standard around purchasing decisions. Utilized with a drone, this combination of photogrammetry and LIDAR can yield the highest accuracy mapping solution.
Accuracy, Accessibility and Adoption
Clients want better accuracy, good full-featured project planning software and an end-to-end solution that is supported. This change in expectation has compelled operators to define exactly how the technology is being used and where it’s creating value.
“Today, most modern drones are equipped with high-quality cameras and use GPS systems to provide accurate location data,” said Diego Barrera, Director of Professional Services for Skyward, A Verizon company. “These capabilities, paired with an aerial perspective, make drones ideal for photogrammetry surveys, and drone programs can recognize the benefits of photogrammetry right away. In many industries, aerial mapping and 3D modeling can be part of the value proposition when calculating the return on investment (ROI) in a drone program, but successful photogrammetry requires safe operation of the drone and effective collection of the imagery.”
Drones are being utilized to produce 2D maps and 3D models via photogrammetry, which includes creating renderings of buildings, job sites, infrastructure and more to capture more information, quicker and cheaper.
“The barrier to entry is lower now,” said Grayson Omans, CEO of Phoenix LiDAR Systems. “The fact that it doesn’t take a million-dollar investment to enter the market means that it’s no longer limited to big engineering firms with big overhead. Smaller companies can offer the service. This is driving the prices and increasing adoption/development.”
Questions around who is consuming this data, how it’s being presented, and who needs access to what type of information, are all being considered in greater detail to further enable the value of the technology.
No More Photogrammetry vs. LiDAR
Because photogrammetry and LiDAR are inherently doing different things, using them in combination is a concept that always made sense. However, logistics and budget often prevented attempts to make this connection. With many of those barriers removed thanks to drone platforms that are cheaper and more powerful, these connections can now be explored in a whole new way.
“LiDAR employs very precise active sensors that generate 3D point clouds by bouncing light beams off of all objects in a scanned area. The light rays can penetrate vegetation to model underlying elements that go unseen by passive, visible light sensors found in aerial cameras. However, equipment costs are generally higher, as is the cost in training employees to use the equipment competently and adapting workflows to accommodate LiDAR-generated point clouds.”
While LiDAR is more accurate than photogrammetry, oftentimes photogrammetry can be the best solution depending on the type of project and the mapping products required. While the possibilities associated with the simultaneous collection and combination of images and LiDAR are more attainable than ever, it’s a combination that really needs to be thought through in terms of hardware, software and process.
Some of the questions that people should be asking when they’re making decisions about utilizing photogrammetry and/or LiDAR for a project include the following:
- What level of accuracy is required?
- What are the deliverables I am generating?
- What is my budget?
- Is a photorealistic 3D mesh required?
- What technology is best fit for the capability of my operators, data processors, end users and company?
- What are the characteristics of the project area?
- How big is the area?
- How is ROI being measured?
- What regulatory challenges or certifications that need to be addressed?
Anyone sorting out whether photogrammetry or LiDAR is right for them needs to ask the right questions and know what they’re getting into. These solutions have proven they can deliver the accuracy as promised, which means adoption is about understanding the applications and limitations of both.