Hello,
I tried out the lossy DNG format with a lot of pictures.
For most pictures I can't find any visible differences.
But I found also some pictures with very noticible visible differences between lossless and lossy DNG.
It seems that the lossy DNG format has problems with dark pictures with small light sources for example
the stars in the dark sky or the red lights of an aeroplane in the dark sky.
I have an example where you can see red security lights of a great antenna on top of a mountain.
Surprisingly with this extreme example the JPG versions looks much better as the lossy DNG version of my source lossless DNG.
Here is the cropped JPG from the lossless DNG (file size 10877KB):
Between this JPG and the lossless DNG file is no visible difference.
And here a JPG from the lossy DNG (file size 13261KB):
Between this JPG and the source lossy DNG file is no visible difference.
The source of both DNG files was a NEF File from a Nikon D7100.
Also interessting is, that for this excample the file size of the lossy DNG is greater than the lossless DNG. This seems crasy IMHO.
I was very surprised, that JPG result is is much better than the lossy DNG for this case.
Perhaps there is a hidden bug in the lossy DNG conversion process.
I hope Adobe can look in to this. If you need the original NEF file let me know.