What is difference between surface and polysurface for my raster image?


Somehow in the restoration of my bak file I now have 4 raster images perfectly on top of each other, all the same image.
Mouse selection gives me the option of tow of them prefix surface - name of raster and two of them polysurface - name of raster.

which ones do I delete to keep just one ?



I would keep one of the “surface” ones… Don’t know how you ended up with images on polysurfaces…



Ok will do, its as if the images are breeding !

I have now opened a layer, get a choice of two groups, ungroup each and I have 3 surfaces and two polysurfaces all the same image. Crazy.



Well, at some point you must have created all those, perhaps unknowingly… I suspect groups, you may not know what you are copying if parts of a group are hidden when you make a copy…