https://proedu.com/products/master-collection-medium-format-sky-cloud-library

The Medium Format Sky Library is a collection of 100 RAW images ideal for photographers very particular about their cloud structure, their light, and their color, and the time of day they want to illustrate. Shot intentionally in medium format, these files will provide you with 14 stops of dynamic range to recover shadows and highlights to give your image the look you are seeking.    We shot these with Architecture and Real Estate photographers in mind, but the files lend themselves as useful assets to portrait photographers, event shooters, and composite artists who have an added interest in making their images perfect with the right skies.  We've provided 100 of the original RAW formats from the Fuji GFX mirrorless medium format camera and have also lightly processes 8K JPEG's for you to use on any image.