@nprofile1q... I saw a thing where these two guys, they couldn't have been older than 25 from how they looked, made a half-spherical canvas out of metal and did some plein air work of the NYC skyline inside of the half-sphere. The whole arrangement was big and heavy. To me, the finished painting didn't really offer anything new in terms of look. It seemed more or less an interesting experimental curiosity to me. Maybe this applies to 3D/irregular canvases as a whole and this is why there are so few.