This format is used by Olympus cameras to create RAW images. These files record data from the camera matrix that are used to generate the image. It contains raw data about contrast, saturation, color temperature, as well as metadata. The exposure and white balance can be changed in an ORF image while maintaining the level of detail and quality of the photo.
PBM is a Portable image in black and white. Can be opened with programs: Adobe Photoshop CS, ACD Systems Canvas 15, ACD Systems ACDSee 17, Newera Graphics Converter Pro, Corel PaintShop Pro X6. File contains 1 bit per pixel. PBM is a kind of file format PPM. And can be readable or binary.