Struggling to work out how to make a depth AND height pass.

Depth is easy...height, not so...

Is there some way to mix a vertical gradient with a mist pass to get this result?

I am trying to get the effect of a denser mist at lower levels.

Let me know if i need to clarify further.

Struggling to work out how to make a depth AND height pass, so I can use them in compositing an animation of a city.

Depth is easy...height, not so...

Is there some way to mix a vertical gradient with a mist pass to get this result? Or is there a different way?

I am trying to get the effect of a denser mist at lower levels.

Let me know if i need to clarify further.

Struggling to work out how to make a depth AND height pass.

Depth is easy...height, not so...

Is there some way to mix a vertical gradient with a mist pass to get this result?

Struggling to work out how to make a depth AND height pass.

Depth is easy...height, not so...

Is there some way to mix a vertical gradient with a mist pass to get this result?

I am trying to get the effect of a denser mist at lower levels.

Let me know if i need to clarify further.