6. Now one can add the Cloud layer behind that of the castle.

7. One will accentuate the contrast of the sky while insisting on the clear zones as if a storm lit the clouds by the top. For that duplicate the Cloud layerand pass the copy in mode Color Dodge.

8. Now it is necessary to harmonize the colors of the two elements: sky and castle. Modify the color of the castle with menu Image > Adjustment > Color Balance, and make your best so that the tone of colors correspond.

9. Then select the Castle layer, and in menu Layer > New Adjustment Layer choose Color Balance. Thanks to this adjustment layer which is created on top of the others, one will be able to change the general color. Give a distressing atmosphere
to the scene.

10. Profit finally to obscure the areas on left of the building with the Burn tool, because they are not exposed to the light of the clouds of right-hand side. It is a rather subtle effect, but that brings a small significant detail.

11. Here is a zoom to understand better.