Video: Academy Coping with Alignment Errors & Misalignment (Lesson 3) with Matterport Content Marketing Manager Amir Frank | Video courtesy of Matterport YouTube Channel (28 September 2017)

Hi All,

If you are just getting started with Matterport, here is Lesson 3 of 11 from the Matterport Academy Coping with Alignment Errors & Misalignment (Lesson 3) (above) with Matterport Content Marketing Manager Amir Frank.

Video Transcript

Hi, I'm Amir from Matterport and today we want to talk about how to avoid alignment errors.

Every 3D scan you capture with the Matterport camera is aligned or placed in the proper location relative to the other scans. Alignment uses the 3D depth data gathered from each scan. When there's enough overlap, then alignment is successful.

When alignment doesn't happen properly, you either get a no alignment error or a misalignment. The most common error you can get is the no alignment error.

There are several reasons why this error can appear. One reason is because there's too much ambient infrared light. The Matterport camera uses a pattern of infrared light to capture the depth data used for alignment. Too much ambient infrared light from the sun makes it hard for the camera to tell what's actually out there. And very little depth data is captured as a result.

Imagine you're building a puzzle, but it has to be built in a certain order. Every scan position is another piece of the puzzle.

If you scan an area with too much infrared light, the captured puzzle piece won't get properly built. And therefore you won't be able to connect to the rest of the puzzle.

Another common reason for no alignment is not enough overlap between scans. The capture app has to find enough similarity in the depth data to align the scan positions. Often times this error happens because there's too much distance between scan positions. In tight situations such as corners and doorways, even shorter distances are recommended.

Mirrors cause alignment problems because the capture app assumes there's another room on the other side of the mirror. Misalignments are trickier to spot than alignment errors because there's no error message. A misalignment can be spotted when a new scan is misplaced in the capture apps preview pane.

This commonly happens in places with empty or repetitive architecture. For example, a large flat wall in an empty warehouse or a long hallway. It's very important to fix misalignments early, because they can cause the rest of your scans to misalign too.

Check the [Matterport] Capture app on your iPad after every scan to make sure the scan correctly aligned. If a scan appears on the preview pane in an incorrect location, delete the misaligned scan immediately. Then move the camera closer to the most recently, properly aligned scan, and scan again. Continue scanning and keep an eye out for future misalignments.

In large, empty and repetitive spaces like an empty factory, it's easy to have misalignments. We have a special guide specifically for this use case at:



P.S. For in-depth Matterport Training, please see the WGAN-TV Training U (in Matterport). We included a 1+ hour training on the Matterport Capture and 3D Showcase Apps by Matterport Content Marketing Manager Amir Frank as well as 6+ hours on Matterport Workshop 3.0 (also by Amir)