Hi Alexey,
My brief experiments indicate the following:
- the overall quality and detail of the mesh is dependent on the initial mesh construction quality (ultra, high, medium, etc).
- details in the mesh can be retrieved by using refine mesh with an ultra or high setting, but course features and overall shape are not affected as much.
It would appear that a good strategy might be to:
1. build the mesh in ultra or high
2. decimate and smooth the mesh to remove noise
3. refine the mesh using ultra or high to bring back details
4. repeat 2 and 3 as needed
I need to perform some more experiments, although I think the refine mesh is outside my capabilities for many of my larger projects - it appears building the mesh is roughly proportional to the number of photos for any given example, while the refine process is not (maybe dependent on the video memory available to the GPU or maybe something else?)
For a 60 camera example I get an ultra mesh build time of 1100 seconds and a refine (10 iterations) of 750 seconds. Yet a big project with over 1000 cameras build the mesh in a few hours while the refine was still going, even after half a day.