LRCC HDR and DNG Lossy Compression

[MBehrens]

While working with the pano merges I've found that converting the -pano.dng to a dng with lossy compression, I can reduce the file size dramatically (100MB down to 10MB)

I don't see this same benefit when I do this with -hdr.dng files. Are -hdr files already compressed? Or is there a technical reason for this? Or maybe it is a bug...

... please don't reply with editorial comments that I need to use a real HDR app, or some other off topic comment... I'm just wondering about this item.

[jrp]

if you go into the Library Mode, you will find that -HDR files are 16-bit floating point tiffs, effectively.  Not sure what the Pano files are (16-bit floats, I think).

Compression just equivalises perceptually similar contiguous parts of the picture.   Since an HDR will have greater variation than a regular or pano photo, compression will have an easier time on the latter.

[MBehrens]

That makes sense. Good point. Thanks.