Scan the site#

Your camera scans continually while you use VisualLive for HoloLens. Good alignment depends on having a comprehensive scan of the site.

Check for poor scan coverage by turning on Wireframe in the Overlay Reality controls. Poor scan coverage is indicated by areas with little or no wireframe (blue lines) visible .

Scan before and during placement#

Scan the entire site before you place your model. Since some areas may be beyond the distance that you can scan, walk around the site and scan areas from different points of view.

Scan after placement to maintain alignment#

Your device will continue scanning after the model is placed.

To maintain the model’s alignment, you need good scan coverage. As you scan:

• Move slowly as you move around the model.
• Avoid covering the lens. Covering the lens in any way causes model drift. The camera needs to ‘see’ the environment at all times and ‘blinding’ it will cause it to lose the model’s place.

HoloLens saves the scan of the environment automatically. When you return to a scanned site to place a model, HoloLens can recognize the location and retrieve the scan.

Minimize problem areas in your scan#

Holes in the scan mesh can occur in extremely bright or dark areas:

• Bright lights (the sun, reflective material, bright artificial lights) can ‘blind’ the camera’s view of the site, particularly if you point the device’s camera directly at them.
• Very dark areas look like empty voids to cameras. If the device can’t recognize that it's looking at something physical, model drift will occur.

Several factors can affect the quality of the scan, and a number of them have workarounds. See Evaluate scanning problems on your site.

Scan before and during placement#

If this is your initial visit to a site that was not previously scanned:

• Scan the entire site before you place your model.
• Some areas may be beyond the distance that you can scan: walk around the site as you scan. Scan areas from different points of view.

In a site that was previously scanned, rescan to:

• Build up the scan mesh in inadequately scanned areas, particularly in areas to be used for alignment.
• Update the scan mesh to reflect changes in the site. Rescanning removes vertices in the mesh that describe surfaces and objects that are no longer there and updates the scan mesh with new information.