Support for the Olympus OM-1 – #34 by Greymont – RawTherapee

Most raw formats are fundamentally organized as TIFFs. That makes the fundamental parsing of file sections consistent camera-to-camera, but the differences in tag IDs and placement may cause need for parsing changes.

After that, it’s the information provided in the metadata to support processing that changes the most, IMHO. For instance, Nikon DSLRs wouldn’t report a decent text lens nomenclature, so raw processors had to engage in stupid pet tricks to divine such. With the new mirrorless cameras, they now populate the EXIF LensID tag quite nicely.

One thing that the major manufacturers have not provided in-raw has been default color primaries. So, raw processors need to keep a large dataset of such for all the supported cameras. Doesn’t make sense, as each cameras’ JPEG engine needs those primaries to produce JPEGs, so they’re in there, somewhere… That’s the main purpose behind RT’s camconst.json file, which you can inspect and modify to your satisfaction, or peril. The DNG format contains tags to provide primaries, and cell phone cameras that use the DNG format usually populate the tags, but the quality of their data has been spotty.

Some things upon which to cogitate…