This format is used for storing photos taken with Swedish Hasselblad cameras. It has a RAW image file structure. It is saved without applying automatic corrections. Photographers can edit the 3FR photos by changing the white balance, color correction, and other parameters without sacrificing image quality.
This format is a vector images file in the Sketch Drawing program, which serves to edit and create interface designs, applications and software shells. SK-files contain objects and layers which can be edited independently of each other.