I’ve managed to render some kind of HDRI image of one of my work in progress models. The problem is there are no reflections! Also it’s quite grainy. Does anyone have any idea what setting I’ve overlooked or set wrong?
The lack of reflections I imagine has something to do with your material settings. In yablex, make sure that the reflection color is added. I think that if the diffuse color and the ref color are further apart, the surface is more reflective. For example, if you want to make a chrome surface, set diffuse color to black and the ref color to white.
The grain is can be reduced by increases the number of samples on your hemilight options. I usually use 8-10.
I’m afraid thats all the help I can offer. bgDM is the one with most of the knowledge regarding HDRI tho.
dante
I’ve solved the reflection problem (thanks dante ;)), but not the grain. I’ve set samples to 12(144) and AA to 4x4 yet it’s still really grainy.
http://www.cyber.brad.ac.uk/~arwest/images/hdri.jpg
http://www.cyber.brad.ac.uk/~arwest/images/space2.jpg
I’ve done a few more test renders and even with samples set to maximum the grain is still there. Does ray depth and bias effect this?
Hmm. I dunno man. What sampling type are you using? I assume your using the normal MC type. I suppose you could try using QMC and see what that does for you… Also you could check out the Yafray doc. I just read the new stuff (photon lights! Yay!) and it was quite helpful… I imagine the problem is obvious but I can’t think of it just now. Like I said before, bgDM knows much more about this then I do…
Sorry I can’t help you more 
dante