Zooming from <10000 meters to 10cm I imported a quite huge model from a GIS with the size of ~10000x10000 metres. Now I want to scale it down to ~10cm. But when I do it, I can´t zoom to my model. At some point the Background raster disapears and I can´t find it.
You need to modify the clip distance, both for the viewport and the camera,
to have a clip distance that uses a much closer range.
See:
How do I increase the render distance?