Quote - > Quote - he problem with pure IBL is that the shadows are awful and unrealistic. Lux does a terrible job of figuring out where the primary light source is even with a really bright sunspot on the HDR. 

I think that Lux actually does a really good job at lighting the scene with the IBl map, but it is true the shadows can be too soft. It's very easy to add a mesh light that is small and therefore creates a sharp shadow. 

This technique was used by a couple of "Skies of Reality" products that were out two years ago.

There is no problem in replicating the technique with Reality's lights today.

Hope this helps

Again though there are issues using mesh lights, the most glaring of which is that it's not an infinite distance away like a source like the sun, so positioning it in relation to the IBL is much more difficult for various reasons. For starters you no longer have the ability to use Daz's 'light cam' to ensure it's facing the right direction, and second of all larger scenes might move out of the light boundaries. The reason I made the presets was to be a lighting solution which works out of the box. The whole concept fails if you're forced to manipulate the light manually, since it would have to be set up again from scratch.

I appreciate the responses and the ideas, but I didn't choose this approach without a reason and was really looking for a way to get Reality to export similar data. I should point out that this is actually an approach which is detailed in the Luxrender Wiki, not just simply random experimentation on my part.

http://www.luxrender.net/wiki/Sun,_Sky_and_HDRI

Again, I must point out that the 'sky' which comes with the sun is essentially just an IBL all of its own. By having a dedicated IBL along with the sun you get your daylight preset, only with much nicer reflections and overall light colour.