Hey guys,
Sure.
The scale thing. the absolute scale of a place ..yeahh, it kind of have to be respected but for big landscapes the farther sections can generally get cheated. There is a degree of flexibility depending on how the camera moves, type of shot or they way is gonna put together ( fully rendered, camera projections, etc ). A lock off cam shot is more forgiving as the end result might just be a projection on a big sphere. In the image i posted of the lake the situation was a bit diferent, it was a simple lock off cam with a 2d push it ( a POV shot ) but the show was Stereo.
And in Stereo scale is a bigger issue altough still forgiving at far far elements so lets say just for saying probably the first 40 km or so are correct and pass that its a bit more of a cheat. Now, as matter of annecdote that particular landscape had very especific topography and i actually had to use terrain elevation data as a starting point. someone higher up arbitrarily picked a piece of the real world and made it our middle earth ! :).
I do remember having some issues with big "real scale" scenes on the software once or twice. I think vray gave me once some sort of error in Maya. i don't think the scenes get heavier at all but i might be wrong. precision seems to go a bit nuts and a bit querky with the clipping planes but that's it.
But there is also relative scale ( that one be barely respect :p ). I could have a tree asset that measures 10mt high and scatter it into a field but maybe it looks like crap in the far distance. then i would just up its scale or whatever makes it look good. i guess we all cheat like that, right?. As far as the final image looks good!.
The paint question. Yes, there is a lot of paint work, in all of them, sometimes just some details here and there and sometimes there is nothing left of any cg elements. In the one area you point out there was a foreground line of moving trees. most likely i had alpha holes from my base renders and quickly filled them with the brush just in case or for presentation. You can see some of the other examples having huge holes which are generally covered by the plate anyways. There is a balance there of how much you can spend building up a 3d scene and where can you take a shortcut. If you are interested i'll be happy to answer about the many sub-processes and gags we do. just let me know.
