What Is Time-Series Comparison of 360° Photos? 7 Ways to Use It to Avoid Missing On-site Changes

In recent years, the construction industry has been advancing work efficiency and promoting DX (digital transformation) through the use of ICT and digital technologies. Along with that trend, methods for recording on-site conditions are also changing significantly, and the use of 360° cameras is receiving particular attention.

Conditions at construction and work sites change day by day. Accurately recording changes due to progress and work, and sharing them with all stakeholders, is key to project success. However, with traditional photo records and written reports alone, it is not easy to fully convey the changes occurring on site. Many have experienced, “I didn’t have photos from the angle I needed later,” or “I have to go to the site to understand the situation.” Especially on large sites or complex structures, it is difficult to grasp the whole picture with just a few photos or written descriptions. Furthermore, conventional methods require substantial effort to organize and manage photos by date and location, and on busy sites photo organization is often postponed, making it difficult to retrieve necessary information quickly.

A promising solution to these challenges is time-series comparison of 360° photos. By using spherical 360° cameras (360° cameras) to capture the entire site and comparing those images over time, you can intuitively understand how the site has changed. If you periodically take 360° photos that record the whole site in a single shot, you can check changes from before work, during work, and after completion without missing anything. Also, because you can virtually experience past site conditions while remaining in the office, the latest status can be shared remotely.

This article explains what time-series comparison of 360° photos means and introduces seven ways to use it so you won’t miss on-site changes. Let’s explore tips to realize site visualization that was difficult with conventional methods and make it easy for anyone to grasp and share site conditions.

Contents

• What is time-series comparison of 360° photos

• Use case 1: Recording and managing construction progress

• Use case 2: Safety management and checking hazardous areas

• Use case 3: Quality control and checking concealed parts

• Use case 4: Remote site monitoring

• Use case 5: Data integration with drawings and models

• Use case 6: Use for routine inspections and maintenance

• Use case 7: Applications for training and knowledge transfer

• Summary

What is time-series comparison of 360° photos

Time-series comparison of 360° photos is, as the name implies, a method of comparing 360° images of the same site taken at different points in time. Using a spherical 360° camera allows you to record every direction of the site in a single shot. For example, in building construction you can shoot a 360° image before starting work and continue to take 360° photos from the same point during and after construction to track changes in detail. In interior renovations you can compare the entire room before and after work, and in civil engineering you can contrast the terrain before and after construction—allowing intuitive confirmation of “Before/After” in various cases.

This method is attracting attention because it helps avoid missing changes on site. With ordinary still images (2D photos), the visible range in one shot is limited, and multiple photos must be taken from different viewpoints. Because humans take the photos, omissions and blind spots occur, and you may encounter situations like “the crucial part wasn’t photographed when I reviewed the images later.” With 360° photos, however, everything around is captured at once, enabling comprehensive records without oversights. Because all directions from the shooting point are recorded, it is also easier to intuitively understand “which location the photo corresponds to,” reducing later difficulty in identifying locations. Furthermore, if these 360° photos are organized and managed in time series, you can arrange data by date and phase and trace changes from the past, making progress tracking smoother.

Thanks to these advantages, time-series comparison of 360° photos is being adopted mainly in the construction industry. In recent years, compact high-performance 360° cameras and cloud-based photo management services have become more abundant, lowering the barrier to incorporating such time-series comparisons on site. So in what specific situations is this method effective? Below are seven ways to use it to avoid missing on-site changes.

Use case 1: Recording and managing construction progress

The most basic use at construction sites is progress management. By shooting the site in 360° at key milestones from before construction starts through completion, you can meticulously record changes in the work in time series. If you keep 360° photos at important stages—before and after foundation work, during structural installation, before and after interior finishing, etc.—you can visually confirm “when, where, and what was done” when looking back later. This makes fine changes that are difficult to convey in documents or verbal reports evident at a glance, allowing site supervisors and project managers to grasp progress based on objective imagery.

For example, in building renovations you can examine changes to walls, floors, and ceilings in full by comparing 360° images of the pre-construction existing state and the post-construction completed state. Even in complex equipment installations, if you record the before-and-after of pipe and wiring installation in 360°, you can verify work on areas that will later be concealed. By continuing 360° shooting in a fixed-point observation format, you can visualize the entire project’s progress in time series and help all stakeholders share a common understanding.

360° photos for progress records are also effective as reporting materials for clients and owners. Changes that are hard to convey with text or planar photos can be intuitively understood with 360° Before/After images. As a result, this can prevent disputes due to misunderstandings and give clients greater peace of mind.

Use case 2: Safety management and checking hazardous areas

Safety management is also a critical issue on construction sites. One useful application is recording safety patrols with 360° photos. If you record conditions with a 360° camera while patrolling the site, staff in the office or at remote locations can later view the footage to check site conditions. Especially in areas that are hard to capture with normal photos and prone to being overlooked—such as high places, narrow footing areas, or around temporary structures—a 360° camera can comprehensively record them in a single shot. By retaining information in all directions so there are no “risks you can’t notice unless you go to the site,” you can later check for safety-related changes or deficiencies.

If a near-miss (near-accident) or trouble occurs, recording the site conditions at that time in 360° can help with root-cause analysis and considering measures to prevent recurrence. Using immersive visual materials allows concrete sharing in safety training and meetings of “what was happening at that spot,” leading to deeper understanding than written reports alone. Accumulating such time-series 360° data will help you avoid overlooking changes in hazardous areas and improve the accuracy of safety management.

Use case 3: Quality control and checking concealed parts

Time-series comparison of 360° photos is also effective for ensuring construction quality. In building and civil engineering sites, many parts and processes become invisible after work is completed. By shooting and preserving 360° images during intermediate stages as records of concealed parts, you can still refer to them later when quality confirmation is required.

For example, conditions of rebar placement before concrete pouring, the layout of buried pipes and wiring, or bolt tightening states—areas that cannot be directly checked after completion—can be reliably recorded by taking 360° photos at each stage of construction. If a question arises during an inspection like “what does the interior look like?” you can virtually reproduce the state at that time by referring to past 360° records. Such photos of concealed parts may also be requested as construction records by clients or regulatory authorities; capturing them in 360° ensures no omissions and provides solid evidence. If construction defects or faults are suspected later, examining the preserved records allows rapid understanding of the actual conditions, helping to prevent unnecessary rework or disputes. This builds a system of checks that does not miss changes or defects affecting quality.

Additionally, 360° photos are useful for recording as-built conditions (the shape and dimensions of completed structures). If you record the finished condition in all directions immediately after completion, you can later compare it with the state after time has passed to detect changes such as cracks or discoloration earlier by referencing the initial state. For quality control personnel, time-series 360° records are important evidence and can help plan future repairs and improvements for similar projects.

Use case 4: Remote site monitoring

Time-series comparison of 360° photos is highly effective when you oversee multiple sites or the site is in a remote location. As remote site monitoring, if you upload periodically captured 360° images or videos to the cloud, headquarters, other branches, designers, and even clients can check the site’s latest status over the internet.

This allows you to grasp progress and changes without visiting each site every time, significantly reducing time and travel costs. For project managers who manage multiple sites concurrently, being able to view each site’s status in time series is a major advantage. By viewing a timeline of 360° photos, you can see what was done where and when without missing anything, allowing you to quickly decide where to concentrate resources. For example, if progress can be confirmed through 360° footage without visiting the site, managers at headquarters and clients can make approvals or decisions at the appropriate time. This simplifies schedule coordination for meetings and inspections and adds slack to the overall timeline.

Sharing immersive all-directional footage remotely also smooths communication among stakeholders. Staff or subcontractors who have not visited the site can discuss while viewing the same 360° footage, reducing misunderstandings and transmission errors and speeding up decision-making.

Use case 5: Data integration with drawings and models

The appeal of 360° photos is not only that they convey the site’s whole picture, but also that they can be used in combination with other digital data. Especially useful is comparison and integration with drawings and 3D models. If you link captured 360° photos to corresponding points on drawings, you can view the actual conditions of that location in all directions while looking at the drawings. If you have 3D models such as BIM/CIM, overlaying 360° photos with model data allows you to visually compare the design assumptions and the on-site reality.

For example, if you overlay a design model on 360° photos taken after steel erection, you can immediately check whether columns and beams were installed according to the drawing and whether there are discrepancies between design and site. Comparing multiple time-stamped 360° images with models can also help trace whether dimensional errors or installation mistakes that occurred in one process were corrected in later processes.

Furthermore, by using survey data linked to photos, you can later calculate distances or areas that cannot be directly measured from the photos. For instance, you can measure volumes of soil shown in 360° images using point cloud data, or compare as-built photos with design drawings to determine quantity differences. By combining visual information with numeric data in this way, you can analyze the site from multiple perspectives. If you link point cloud data or as-built measurements obtained on site with photos, you can review the site comprehensively, including numerical information that cannot be measured from the images alone. Such data integration makes it possible to capture site changes from both visual and numerical aspects.

Use case 6: Use for routine inspections and maintenance

Time-series comparison of 360° photos is also valuable for maintenance of completed structures and facilities. Buildings and infrastructure deteriorate over time, and small changes accumulate; if you record 360° photos during routine inspections and accumulate the records, you can accurately capture the course of aging changes.

For inspections of large infrastructure such as bridges and tunnels, similarly taking and accumulating 360° photos during regular inspections allows long-term monitoring of deterioration. Information that used to be left only in inspection reports or partial photos can now be stored as imagery of the entire space, effectively reducing oversights and record omissions. Also, when the next inspection references the 360° record taken at the previous inspection, deterioration can be accurately handed over even if the inspector changes. For facility owners, visualizing changes from the past makes planning repairs easier.

For example, if you take fixed-point 360° photos of a completed building every six months or annually, you can catch gradual changes such as the appearance and expansion of cracks, paint deterioration, and progression of rust or dirt on equipment. Inspectors can compare the previous 360° image with the latest state to detect early signs of deterioration and plan maintenance at the appropriate time. Recording equipment at heights or in confined spaces with a 360° camera also reduces dangerous work at heights while allowing detailed later confirmation, contributing to improved safety.

Accumulated all-directional inspection records in time series are useful for planning future repairs. Analyzing the accumulated data as a “health check history” for buildings and equipment helps identify which parts are deteriorating at what pace, enabling optimization of long-term maintenance costs.

Use case 7: Applications for training and knowledge transfer

A 360° photo archive is valuable for training and skills transfer. If you record on-site events, excellent construction procedures, or failure cases in 360° footage, you can later share them with new staff and young technicians with a strong sense of presence. Because you can preserve “the atmosphere at that place and time” that is difficult to convey with written reports or still photos, learning efficiency increases dramatically.

For example, if you keep a 360° video of a particularly challenging construction task that was successfully completed, it becomes precious teaching material that allows newcomers to retrace the steps of veterans. If you record site conditions when a near-miss or accident occurred and use them as training materials, safety education gains realism and helps develop the ability to detect hazards. If time-series site records are accumulated, it becomes easy to learn from the past and apply the lessons to the future. By turning veterans’ knowledge and on-site know-how into video assets, you can share skills across the organization and accelerate knowledge transfer that tends to be person-dependent.

Thus, accumulated 360° on-site archives serve as a database of site experiences. Being able to virtually experience past cases in training and review sessions provides practical knowledge that paper materials alone cannot offer. Sharing veterans’ know-how and on-site presence through 360° footage greatly contributes to more efficient talent development and accelerated technology transfer.

Summary

Time-series comparison of 360° photos is a powerful method for accumulating comprehensive visual records of every corner of a site and capturing changes over time without missing them. Its usefulness extends across progress management, safety management, quality checks, remote monitoring, data integration, maintenance, and training. This approach is attracting attention as an initiative that supports i-Construction and promotion of DX in construction sites advocated by the Ministry of Land, Infrastructure, Transport and Tourism, and it is expected to significantly contribute to improving on-site productivity and labor saving. Changes on site that were previously overlooked can now be reliably understood—what happened, when, and where—by reviewing 360° all-directional images.

To maximize the effect of 360° photos, it is important to record them with accurate position and time information. Thoroughly enforcing fixed-point shooting and properly managing shooting dates and locations increases the reliability of time-series comparisons. A useful tool for that is the GNSS device “LRTK,” which can be attached to a smartphone to easily realize high-precision positioning. LRTK is a small positioning device that attaches to an iPhone and, using real-time kinematic (RTK) technology, can reduce positioning errors to several centimeters (several in).

For example, with a single button operation you can measure the current elevation or easily tag and save the coordinates of the spot you photographed with your smartphone. The acquired positioning data can be instantly shared and centrally managed in the cloud with photos and drawings, directly improving efficiency in site record keeping.

By combining high-precision position information with 360° photos, you can track on-site changes more accurately in both spatial and quantitative terms. Advanced site management that links drawings and point cloud data becomes easier, directly contributing to project efficiency and quality improvement. In addition to time-series comparison of 360° photos, consider using tools like LRTK to further enhance the accuracy of site records and operational efficiency.