Export Heightmap

How do I export heightmap to .png or TIFF and get a detail map.
Do I normalize?
Do I center the heightmap?
It get to dark or to white an looses detail
What to to ? Workflow? Help if possible to overcome this

The output node already lets you export as ,png, .tiff and many more, and the amount of detail in it depends on the resolution you have built the world. There’s nothing complicated behind it.