What does [R] behind model name means?

[toffersan]

Hello agisofter!
What is the meaning of [R] behind the model name?
All my single chunks had the [R], but after saving my project, open the project again, some of the chunks lost this [R] and the models seemed kind of lost, they are not visible in the model pane anymore, even re-setting view did not help. What happened to the chunks without this [R]? The rest of the chunks are still fine.
Greetings Toffersan

[Alexey Pasumansky]

Hello toffersan,

[R] mark means that the chunk is Referenced. It may appear if you are using referencing information (coordinates of the cameras or markers) or have aligned several chunks with each other using Align Chunk option.

[toffersan]

Hello,
yes all chunks were referenced and i aligned chunks, but how can the [R] and though the referenced status of the chunk get lost and why its is not possible to display the chunk anymore. In the reference pane the gps and altitude Infos are empty now.