Better colour accuracy. All my HDRi skies were shot with a Canon 1dsmk3 so I like to keep as much as possible of that information preserved in the HDRi file. Radiance (.hdr) is limited to sRGB colour data, whereas OpenEXR (.exr) is not.
This is reflected in the file sizes:
For this skydome for example
the exr file size is 160mb, the hdr version is 50mb
That said, I have decided to start including a .hdr version in the products I am selling on 3docean. I’m still updating all the files, but check back soon and if you have bought one of them you can re-download a new version for free.
Why hdr? Unfortunately some applications don’t support exr, so until they do you can use hdr (albeit in the knowledge that your colours might not be quite as lovely*)
* not scientifically tested!
