Here is an example of how to adjust the sky/ground transition in an image with a flat horizon:
1. Result with default adjustments
Image obtained with the default settings of the "Blend" module. The result is acceptable, but the sky/ground transition does not look quite natural (especially in the sky area). The first thing to do to start adjusting the sky/ground transition is to check that the general adjustments (the red arrow button) are selected.
2. Adjusting the sky transition
When the horizon is flat, practically by adjusting the sky transition a little, a perfect fusion is achieved.
3. Adjusting the exposure balance
As the horizon area was a bit too light (compared to the rest of the sky), it was decided to reduce the exposure balance a bit (so the horizon brightness is more in line with the rest of the sky).
4. Adjusting the ground transition
The radius of the ground transition is increased a little so that the foreground is not so bright (by making the transition area larger), thus making the image completely finished.
Magnification of a region of the horizon (at 100% zoom) to show in detail the result of the transition between the sky and the ground.