I would like to enthusiastically request that Adobe release codecs (for Windows at least) that can decode all variants of DNG that they have developed. And that Adobe clearly communicate which variants of DNG are proprietary, and work only in Adobe products, and which are standardised and supported by codecs.

I was under the impression that Adobe is promoting DNG as an open standard, and I bought into that. I converted my most recent batches of CR2 files to DNG, with the lossy and fast load options (after a few tests, I became convinced that DNG lossy is a viable space-efficient HDR format). Only to find that the DNG files cannot be decoded by Windows picture viewers, or (in my experience) any 3rd party picture viewers or editors. At best, they can display the embedded JPG preview. Yes, I've installed the Adobe DNG codec for Windows.

So after doing some web searches about the problem, I find a consensus that DNG with lossy or fast load options is a completely proprietary format, that has no public codec or documentation. And yet when I converted my raw files in Lightroom, and was presented with those options, I was not informed that they would render my files unusable by any non-Adobe image viewers or editors.

Adobe: fix this. Why did you create unsupported DNG variants? I thought that was a company mission, to promote DNG as a standard. And why does the Lightroom DNG conversion option not state which DNG versions are compatible with released codecs?

On a related note, how should I choose which DNG version to use? 6.6? 7.1? Should I decide based on numerology, or the day's lotto results? How about some actual info on what the advantages and/or incompatibilities of each version are?