Hello everyone,
I have two datasets, referring to the same facade of a building:
laser scans (Riegl, exported in .ptx with reflectance values): they are 2 scans = 12 lsp;
photographs (jpeg) 141 images.
RC fails to align the two datasets into a single component. He always creates two separate ones.
I tried to insert Control Points (I hope the right way!) but it still doesn’t work.
As an example of the procedure performed: I created a Control Point on an image (2D view) of the first data set. I then dragged and dropped the same point in the other images in which it was present, always in the first data set. I continued the process for the images of the second data set. I deleted those images in which I was showing a projection error higher than the threshold. I then launched “Align Images” again.
in my experience it CAN be possible to align scans without color, but then the conditions have to be ideal. If it doesn’t work out of the box, the chances are hight you won’t be able to coax it into merging the components. And if, then the results will probably not be ideal. If you post two screenshots of the sparse pointcloud of the two data sets (and maybe a sample image of an image and an lsp), we might be able to evaluate the situation better.
Hmm, at first I thought that the angles are too different for it to work, even if you had RGB colors in the scan. But then I noticed that your sample images are from almost the same spot as the scan. My theory is that RC treats each scan as 6 images, into which each station is transformed. The resulting cubes seem to be aligned to the main axes of the coordinate system to which you have geo-referenced the scans. This seems to be at roughly 45° in relation to your facade, which in turn results in an image with a crass vanishing point effect. And this is very bad for photogrammtery to match. So there might be a chance that if you arrange the coordinate system parallel to the facade (if you are able to do that) it might work better. This is really only a guess on my part so don’t put too much hope into it.
Thank you for the tip! Finally, I managed to solve. I added other control points and on the third attempt at alignment, RC succeeded! Thanks for your help
