Originally posted by photolady95 I always shoot RAW and .DNG.
There normally is no good reason to do so.
The downside is doubling one's storage requirements and probably also making the camera slower in clearing the buffer.
The only reason for keeping raw (PEF) versions in addition to DNG files is to accommodate software that only offers generic DNG support and reserves some functionality for camera-specific raw formats. Often, however, software distinguishes between camera-generated DNG files versus generic DNG files that are the result of running the Adobe DNG converter on camera-specific raw files. The camera-specific DNG files then typically receive the same support as the native raw formats.
So in summary, shooting DNG only has definite advantages (e.g., not being required to update software in order to get support for a new camera model) and only in rather specific cases PEF files can bring additional value.