In short, "they are images with multiple light settings embedded... so when you use them as environment in 3d... they adapt their light quality to the scene..."

Some relevant information (pretty technical):
HDR VolVis: High Dynamic Range Volume Visualization

I know about a website where you can get some for free. I don't have the link here but I will post it tomorrow from work. What 3D soft are you using?
(bloody hell... where's the 3D subforum? )

c4d, and yes ... where's the subforum for 3D haha! tia for the links, greg57.

I've asked for it. (indeed I was a bout to move your topic and... oh no! There it wasn't!)

i was comtemplating to post in Vids, here(Photo) or just simply openspace. then decided here.

Not anymore, the 3D category has been created and the topic moved into it

Ok, here's a website with free hdri skies. Can't finf the one I was looking for, though

Hum... it seems there is a dead link out there...
You might also want to have a look at these.

here goes the 3D subforum
it should have been there since the beginning.

And another one. Not skies, mostly for realistic reflections on metal looking materials...
Gosh... can't find that bloody page anymore.

... Yet another one (but still not the one)...

Thanks to both, greg57 and linathael.

Here are some links which might help for free hdri downloads...

http://www.lightworks-user.com/hdri_starte...realtexture.htm

http://www.hdrmill.com/Freebies.htm

http://www.c4dzone.com/texture_e_materiali.php *need to login

http://gl.ict.usc.edu/Data/HighResProbes/

http://unparent.com/

http://www.bencloward.com/textures_extra.shtml


grafxflow

grafxflow, thanks!