Too pronounced or barely visible displacement in rendering, may indicate wrong displacement settings in your Corona material or in Render settings. Make sure that:
- Displacement's min/max level values in your material correspond to scene units you are using (i. e. the value is not too high nor too low in relation to the object's size)
- Displacement's "Water level" value is set to 0
- In Render setup > Common tab under "options" section, the "displacement" checkbox is checked
See also: