Heightmap resolution based on geometry and zoom lvl.

[Yberon]

Hello,
Why heightmap resolution is based on zoom level?
i.e. When i generate zoomed (with L lock) terrain it's more detailed than bigger one.
Shouldn't heightmap resolution be locked on it's limit (90m) all the time?: [larger area=bigger heightmap resolution]?
Larger areas are almoust no detiled because of low geometry of the plane -further subdividing does not help at all.
How to create bigger area in that case? Generate small tiles and stitch them?

[AnotherOneOleg]

I also do not understand how to make the mesh density higher. The mesh density is always the same even when I take a huge area that includes the city and the surrounding mountains.