The best place for technically perfect Log or RAW files is directly from the source. Manufacturers provide these so editors can test their sensors' dynamic range.
Finding high-quality LOG footage for color grading practice is essential for mastering tools like DaVinci Resolve. The most reliable sources for free LOG and RAW files are the camera manufacturers themselves, as they provide high-end cinema-grade samples to showcase their sensors Official Camera Manufacturer Samples log footage for color grading free download