Efficient Management of Field Survey Photos with GPS Coordinates

Table of Contents

• Challenges in managing field survey photos

• Benefits of photos with GPS coordinates

• Methods for managing photos using GPS coordinates

• How the fusion of smartphones and high-precision GPS is changing site management

• Simple surveying with LRTK

• Summary

• Frequently Asked Questions (FAQ)

Challenges in managing field survey photos

At construction sites and during field surveys, many photos are taken to record progress and conditions. Organizing and managing these field survey photos is an important task, but conventional methods have several challenges.

Typically, after returning from the site, photos taken with digital cameras or smartphones are imported to a PC, sorted into folders by date or site, or pasted into spreadsheet-based reports for management. However, this work is very time-consuming, and on days with many photos it is not uncommon for renaming and pasting alone to take more than an hour. For many sites, photo organization becomes a daily task and a cause of overtime work.

There is also the problem that the link between photos and their shooting locations tends to become ambiguous. After some time, you may forget “where on the site was this photo taken?” Especially on sites with many similar facilities or scenery, simply looking back at photos may not be enough to identify the shooting point, causing confusion when preparing reports. Many people have likely experienced not knowing which photo was taken where.

Additionally, sharing site photos within a team can be inefficient. Relying only on file names or notes to convey photo locations has limits, and recipients may find it difficult to understand where a photo was taken. For example, when dozens of photos are taken in a single day, searching for the desired photo later using only folders and file names is difficult. As a result, there are cases where people end up reattaching photos to reports while cross-checking handwritten notes, consuming a lot of time. A practical solution to these problems is to attach objective location information to photos for management.

Benefits of photos with GPS coordinates

If you attach and manage positional coordinates such as latitude and longitude to photo data, you can address the aforementioned issues. Here are the main benefits of giving photos coordinate information.

• You can tell the shooting location at a glance: If latitude and longitude are recorded in the photo file, you can later plot them on a map to immediately confirm “where the photo was taken.” Because you can grasp the positional relationships between photos, you can create more persuasive reports with maps attached.

• Information sharing becomes smoother: With GPS-coordinate photos, recipients can also check the point on a map. For example, if you upload photos to the cloud and allow stakeholders to view shooting locations on a map, you can intuitively share site conditions.

• Useful for work records and proof: Since photos objectively retain “when and where they were taken,” they can be used as proof that work was performed at the designated location. Using GPS-tagged photos for construction records, equipment inspections, or cleaning tasks makes it easier to demonstrate that work was carried out, leading to more reliable reports.

• Streamlines photo organization and analysis: Using coordinate data, photos can be automatically classified or listed based on location. It becomes easy to automatically sort photos by site or analyze shooting point distributions on a map. In other words, digitization and automation of photo management advance, reducing staff workload and expanding opportunities for data utilization.

By adding GPS coordinates as metadata to photos, the accuracy of field survey photo records and management efficiency improve dramatically.

Methods for managing photos using GPS coordinates

So how should you actually manage photos with GPS coordinates? Below are three basic steps from field shooting to in-office sharing.

• Record GPS information in photos on-site First, set your device so that location information is recorded when taking photos on-site. When using a smartphone camera, enable location services (GPS) in the device settings and allow the camera app to use location information. This will automatically save latitude and longitude to the photo file’s EXIF data at the time of shooting. Recent smartphones have high-precision GPS built in, so you can easily take photos with location information without special equipment. If you use a digital camera without GPS support, you can record coordinates simultaneously with a handheld GPS logger or a smartphone app and later attach them to photos (described below).

• Organize and store photo data After shooting, organize and store the photo data. Basically, separate folders by project or site and use file names or subfolders that make the date and content easy to understand. Because the shooting location coordinates are embedded in the photo file, there is no need to force coordinates into file names; however, including the site name and year/month in folder names, e.g., “202303_SiteName,” makes later searching easier. It is recommended to also save photos to cloud storage for backup and team sharing. Note: location information may be removed when sending photos via email attachment or SNS (for example, some SNS automatically delete location data on upload), so share the original data as needed.

• Visualize and share photos on a map GPS coordinates included in photos demonstrate their true value when used on a map. On a PC, open an online map service such as the Geospatial Information Authority’s map, input the photo’s latitude and longitude to confirm shooting points, or import a photo list into GIS software to display them all on a map. If there are many photos, it is convenient to automatically generate a KML file (a location file for map software) from photo metadata and plot them on a map. Visualization on a map lets you intuitively grasp “what photos were taken at which locations,” smoothing information sharing among stakeholders. Also, using cloud services or apps for site photo management can automatically upload photos to the cloud at the time of shooting and automatically create map-attached reports, enabling more advanced and efficient workflows.

Note: If GPS location information was not recorded in a photo, you can still add it later. If you know the latitude and longitude of the shooting location, you can append those coordinates to the photo’s EXIF data using free PC software. Complementing photo data with location information based on addresses noted on-site or points on a map is a good practice.

How the fusion of smartphones and high-precision GPS is changing site management

In recent years, new solutions that combine smartphones with high-precision GPS technology have emerged, bringing major changes to field surveys and surveying. Previously, consumer GPS with meter-level errors was insufficient for high-precision positioning, and specialized expensive equipment and skilled surveyors were required. Now, however, by simply attaching a palm-sized high-performance GNSS receiver to a smartphone, anyone can measure positions with centimeter-level accuracy (centimeter-level accuracy (half-inch accuracy)).

The fusion of smartphones and small GPS receivers has made on-site positioning and data recording dramatically easier. Accurate coordinates can be measured with a single tap on the smartphone screen, and measurement data can be digitally recorded and uploaded to the cloud immediately. Tasks that used to require two surveyors to set up heavy equipment or record on paper field books can now be completed with just a smartphone. Moreover, surveying work that previously required two or more people can now be completed by one person, enabling many control points to be recorded in a short time. Time spent setting up and packing heavy equipment is reduced, and the ability to measure whenever needed enhances operational agility.

For example, it is easy to attach photos and notes to each measured point on the spot and manage them centrally. Data that links location information with photos and text can be shared in real time on the cloud, allowing office staff to instantly understand site conditions. Because smartphone apps can automatically handle coordinate transformations and drawing generation from survey results, information linkage between the field and the office is greatly streamlined.

Furthermore, using cameras and LiDAR sensors built into smartphones, it is possible to capture site conditions as three-dimensional point cloud data. By taking multiple photos or performing LiDAR scans, you can create 3D models of terrain and structures on-site, so 3D recording that previously required specialized equipment and time can now be completed quickly with a smartphone. Point clouds acquired in this way are tagged with high-precision positional coordinates, making them immediately useful for excavated earth quantity calculations or deformation measurements of structures. The miniaturization of surveying equipment and smartphone integration has advanced field record methods to this extent.

Thus, the latest technologies that utilize smartphones and high-precision GPS dramatically improve efficiency and data accuracy in managing site photos and positioning tasks. Next, let’s look at simple surveying using one such solution: LRTK.

Simple surveying with LRTK

LRTK (pronounced "L-R-T-K") is an ultra-compact RTK-GNSS surveying device designed to attach to and be used with a smartphone. It is integrated with a smartphone case and can be attached and detached with one touch, so you can quickly mount it on a smartphone when needed. The device itself is very lightweight at approximately 125 g and does not add much burden to carrying the phone. It is designed to work with the smartphone’s camera and communication functions so anyone can easily perform high-precision positioning. When used with a dedicated smartphone app, you can obtain centimeter-level coordinates with the press of a button, without complex settings or specialized knowledge (centimeter-level accuracy (half-inch accuracy)).

For example, if you bring LRTK attached to your smartphone to a site, you can perform accurate surveying on the spot without preparing heavy tripods or surveying instruments. Simply tap the app’s “Positioning” button at the point you want to measure, and you will receive positioning results with automatic calculation of latitude, longitude, and elevation. The measurement point automatically records the date and time, and you can enter point names or notes as needed and attach site photos taken with the camera. Because the smartphone’s electronic compass can be used to record the photo’s shooting direction, it is also convenient that you can later see exactly which direction the photo was taken.

The surveying data obtained in this way (coordinates, photos, notes, etc.) is automatically uploaded to the cloud and centrally managed securely. There is no longer any need to record on paper field books or re-enter data into a PC after returning to the office. Results from the field can be viewed immediately from the office PC through a browser, and data can be exported to CSV or common CAD formats as needed. Because data sharing is completed at the moment of measurement on-site, report preparation speed improves dramatically.

By introducing simple surveying with LRTK, surveying and location-recording tasks that used to be difficult without specialized contractors or expensive equipment can be easily performed by on-site staff themselves. In other words, single-person surveying becomes possible. LRTK is a powerful ally in situations such as routine inspections where “I just want to measure here” or in disaster investigations where you need to quickly and thoroughly record site conditions. Because high-precision coordinate data and photos can be linked and acquired on the spot, LRTK is also very useful for efficient management of field survey photos. Actual use of LRTK reduces time spent on photo organization and measurement tasks, contributing to overall operational efficiency and quality improvement.

Consider adopting new site management solutions that leverage location information and ICT to improve efficiency and sophistication.

Summary

Managing photos with GPS coordinates is a key factor directly linked to reducing burden on site operations and making effective use of data. Organizing site photos, which used to be cumbersome, can be made significantly more efficient by leveraging location information, greatly reducing on-site staff workload and decreasing human error. Furthermore, the combination of smartphones and high-precision GPS makes precise surveying accessible to anyone, and we have entered an era in which photo records and survey data can be managed together. By utilizing solutions such as LRTK, site DX (digital transformation) will accelerate, and the speed of report preparation and the quality of information sharing will improve dramatically. Collaboration between field and office should become smoother than ever. Take this opportunity to work on the efficient management of field survey photos with GPS coordinates. Make GPS and IT your allies and transform site record-keeping smartly.

Frequently Asked Questions (FAQ)

Q: Will GPS coordinates be recorded just by taking photos with a smartphone? A: Yes, in most cases taking a photo with a smartphone will automatically record location information (latitude and longitude). However, you must first enable location services on the smartphone and grant the camera app permission to use GPS. In places where GPS signals are weak at the time of shooting, coordinates may not be obtained, so it is more reliable to shoot outdoors with a clear view of the sky or confirm that the GPS has captured your current location before shooting.

Q: If old photos lack location information, can I add it later? A: Yes. If you know the latitude and longitude of the shooting location, you can embed that location information into the photo data afterward. For example, there are PC free software and smartphone apps that allow you to designate the shooting location on a map and add geotags to photos. You can write coordinates into many photos at once, though it can be time-consuming; therefore, it is recommended to make it a habit to enable camera location information when shooting in the future.

Q: How accurate is a smartphone’s built-in GPS? How can I achieve higher accuracy? A: A typical smartphone’s GPS accuracy is said to be on the order of several meters (in some situations errors of about 5–10 m (16.4–32.8 ft) may occur). This is sufficient to indicate a general location on a map but is insufficient for detailed tasks such as setting out construction reference points or precise surveying. For higher-precision positioning, use surveying instruments that support correction techniques called RTK-GNSS. For example, using a smartphone-mounted device like LRTK introduced in this article enables position measurement with errors of only a few centimeters (centimeter-level accuracy (half-inch accuracy)).

Q: How can I plot photos on a map to check their locations? A: If photos have location information, you can display them on a map in several ways. One simple method is to read the latitude and longitude recorded in the photo’s EXIF and search that coordinate in an online map service to display the location. If you want to map multiple photos, generate a KML file (location information file) from photos and load it into an online map service, or import a photo list into free GIS software to plot them. Even without specialized GIS software, you can use various free tools to visually confirm and share shooting locations. There are also free online services that can plot pins on a map from photo location data, so trying such tools is an easy option.

Q: What should I be careful about when sharing photo location information externally? A: Location information embedded in photos may relate to privacy or confidential information. While convenient, sharing photos externally can lead to unintended information leaks. Therefore, handle photos with care when providing them externally or posting them on SNS. Many SNS and chat apps automatically remove location information at upload for security reasons, but when using photos in reports for clients or partners, consider removing location data from EXIF beforehand. In cases where you do not want to disclose the exact site, creating a copy of images without location information for sharing is an effective countermeasure.