When Adobe's V4 DNG Camera Profiles (DCP files) came out, I blogged about the new fields in this post. Well, the good news is that Adobe did eventually document the new fields, and now dcpTool is updated to support them.
For reference, the three new fields are:
- Exif 0xc7a4 : ProfileLookTableEncoding, which defines whether the LookTables are in linear or sRGB encoding,
- Exif 0xc7a5 : BaselineExposureOffset, which allows the profile to specify an exposure offset, and
- Exif 0xc7a6 : DefaultBlackRender, which is a "hint" to the raw converter as to whether or not to perform black level subtraction. (Black level subtraction can interfere with LookTable operation. Not that I think that a "hint" has any place in a specification, but the Adobe folks don't agree with me on that.)