Timeline: Compare 3D Models and 2D Maps

The Timeline feature lets you visualize site progress by comparing 3D models and/or 2D maps of the same location captured at different points in time. By tagging assets with "Location" names, you can easily perform side-by-side comparisons and track changes over time.

Comparing a bridge captured on May 01, 2023 with the same bridge captured on October 21, 2025

1. Organizing Assets with Location Tags

To use the side-by-side Compare feature, you’ll first need to assign one or more assets a Location Tag. A Location Tag can be any name you choose, but we recommend using the name of the site (e.g., Golden Gate Bridge, Eiffel Tower, 14th Street Building).

Assets must share the same georeferenced EPSG code to compare them with one another. If an asset was not properly georeferenced (for example, indoor room captures), you can still use the Compare feature, but you may need to align the models using third-party desktop software before uploading to Nira.

2. Using the Timeline UI

Once a Location Tag has been assigned to one or more assets, the Timeline button will appear in the top of the viewer interface. Clicking it provides two main options:

• Compare: Opens the slider interface to enabled the side-by-side comparison

• Open: Quickly opens a specific asset that shared the same Location tag

3. Managing Capture Dates

Assets in the Timeline menu are ordered based on the Capture Date assigned to each asset.

• Metadata Accuracy: When you upload images, Nira will automatically assign a capture date based on the image metadata (EXIF).  The Capture Date reflects the actual state of the site on the day of the survey, as the date is derived from the source photos, not the 3D reconstruction or upload date.

• If you don't upload photo(s) with your 3D Model or 2D Map, you can manually assign a capture date.

4. The A | B Split Compare View

When in Compare mode, assets are displayed in a split-pane view.

• Side A (Left): The reference asset (the one you started with)

• Side B (Right): The asset you selected to compare against

• The Slider: Use the central slider to dynamically adjust the size of each pane and see changes in real-time

Change Side A or Side B to another asset that shares the same Location Tag from the Layers panel.

Within the Hamburger menu, you can choose Horizontal or Vertical split.

Exit Compare mode will Close Side B, essentially closing Compare Mode.

Annotating while in Compare Mode

While in Compare mode, you can create Callouts and Measurements by clicking on either Side A or Side B to place them on the corresponding asset.

Sharing Your Comparison

The URL includes the assets currently active in Compare mode. Simply copy and share the URL to share the comparison.  Keep in mind that anyone you share the link with must have access to both assets, either by setting them as Publicly Accessible or by adding the person as a user on each asset.

Pro Tip: You can also compare an asset with itself to view two different Variants of the same model side-by-side.

5. Troubleshooting & FAQ

Why isn't my Timeline button appearing?

The Timeline button only appears if the asset you are currently viewing has been assigned to a Location tag. Double-check the Capture Details settings to ensure a tag is applied.

My models aren't aligned when I move the camera. Why?

This usually happens if the models use different coordinate systems or if the georeferencing is offset.

• Solution: Ensure all assets in a Location Group use the same Coordinate Reference System (CRS). If the models are not georeferenced (like indoor scans), use the Alignment tool to manually sync their positions so the cameras track together.

The Capture Date is wrong. Can I change it?

If your camera’s clock was not set properly or the EXIF data was stripped during processing, the asset may appear in the wrong chronological order.

• Solution: You can manually edit the Capture Date in the asset’s Capture Details settings.

Can I compare assets from different Locations?

Nira only allows comparisons between assets within the same Location. If you need to compare assets from different Locations, you will need to add them to a shared Location tag first.  There are no limits to how many Location Tags you can have per asset.

Does the Timeline work on mobile?

Yes! You can use the slider and A | B view on mobile devices.

Important Notes:

The Timeline Compare feature is only available for Professional, Growth, and Enterprise plans.

Photo inspection isn’t available in Compare mode, but this feature is planned to be supported in a future update.

Panoramic photos within E57 laser scans are not accessible in Compare mode, but support for this is planned in a future update.

Inspection Links do not work with Compare mode.  If you would like to share an asset and preserve annotations (Callouts or Measurements) created by whomever you share it with, it's important you add that person as a user to each asset with Edit privileges.

Be sure to follow this article to be notified of when we make updates to this feature.