Most digital cameras use lossless compression with raw files. That means the size of raw files from the same camera is somewhat content dependent.

The more detail and different colors a scene contains, the larger the file will be. The more homogeneity a scene contains, the smaller the file will be. The degree of the differences will also be governed by differences in things such as noise in dark areas (noise usually adds to a file size by creating a greater number of unique brightness levels).

Many digital cameras use lossless compression with raw files. That means the size of raw files from the same camera is somewhat content dependent.

The more detail and different colors a scene contains, the larger the file will be. The more homogeneity a scene contains, the smaller the file will be. The degree of the differences will also be governed by differences in things such as noise in dark areas (noise usually adds to a file size by creating a greater number of unique brightness levels).