Point Cloud loses georeference after chunks being merged

[Thorin]

Hello,

I'm facing a problem after merging two (or more) chunks each of which consisting of individual tie points and a point cloud, which were individually georeferenced.

For the documentation of an archaeological site i conducted 8 different series of photos over the course of several weeks, each serie has to be processed as a separate chunk, with it's own markers for georeferencing. This all works well, and I now have 8 different chunks with georeferenced tie points and point clouds.
Now I want to merge all the chunks in order to get one complete model of the site.
However when I'm merging chunks together one of the two point clouds in the new chunk will lose it's georeference for whatever reason (see image 2). The tie points of these single chunks are merged together and become one big tie point cloud which is georeferenced as it should be (see image 1).
The individual photos and markers which are part of the "lost point cloud" are all still placed correctly.

I really have no idea why the point cloud lost its georeference and I don't know how to fix that.

[Alexey Pasumansky]

Hello Thorin,

Can you please also share the screenshots of two original chunks in Show Aligned mode in Model view both for tie points and point cloud.

And specify Metashape Pro version (including the build number) that you are using.

[Thorin]

Hi Alexey,

thanks for your fast response!

In both chunks the tie points and the point clouds are aligned with each other (see image 4 and 5).

I'm using version 2.0.0 build 15597 (64 bit).

[Alexey Pasumansky]

Hello Thorin,

Do you have the possibility to try the same merging procedure in 2.1.4 or 2.2.0?

[Thorin]

Hi Alexey,

I finally found the time to update my Metashape install to the latest version 2.2.0 (build 19890) and repeated the "Merge Chunks" step. This time with a slightly different result.
When I check the option "Merge assets" it generates a combined point cloud from the two chunks with a correct georeference (see image 6).
However, when I uncheck the option "Merge assets" (since I want to have two seperate georeferenced point clouds in the merged chunk) the software generates the two point clouds, but one of them still lost its georeference (see image 7), and one combined point cloud with the correct georeference.

The reason I need two separate point clouds in one chunk is, that I want to be able to delete points from the individual point cloud in those areas where both point clouds have an overlap, before I merge them into one point cloud, in order to be able to generate a cleaned / non overlapping model out of this combinded point cloud.