Thanks for the props. You have done perfect job of explaining, thanks. Where you are lacking, is in understanding that I have explained this to you many times now.
Allow me to re-state what I have already stated in post #28.
1. You can color match the new cloud layer to the original layer.
2. You can color match the original layer to the new cloud layer (like I did in post #14).
3. You can change both layers with an H&S, Curves, or Selective Color adjustment layer. If you change both layers, you will have to use a clipping mask. In other words, you will have to clip the adjustment layer to the layer you want it to affect. In doing so, the adjustment will not affect the layers below the layer it is clipped to.
If you have 4 panels, you will have to do one of the above to all 4.
I can't help you with this thing you refer to as homogeneous until you have posted an example.
However, I can tell you this, it should NOT matter! If you are doing what we have been discussing, there is no need to closely match a single cloud to that of the original layer. Clouds are white and grays and sky is blue................all you need to do is get the blues close enough that it's not so noticeable.
Before you respond, PLEASE post images of what you are doing. I fear you are making this much more complicated that it needs to be.
