Inspiration from my favorite filmmaker Hayao Miyazaki.
Modeling, lighting and rendering in Blender. Clouds could probably have been photo bashed, but I created and rendered them in Houdini to learn the software, and composed them into the Blender render in post.
Thanks everyone for your messages, and @bartv for featuring my work
@alekba & @MagnussonProductions thanks for noting the broken link. I’m indeed updating my web presence, using from now my real name instead of a pseudonyme, and Artstation link changed indeed.
@Charles_Weaver Yes, clouds are volumes. I rendered only 1 frame and then animated it with a warp tool in compositing, as rendering a sequence would have taken ages on my computer.
Honestly, this wasn’t the best workflow for this image. I did it only because I wanted to learn more about the volume rendering techniques, but normally for an image like this, I believe that photobashing the clouds in post would be better and faster.