I bought this set some time ago when it was on sale, but haven’t really tried to use it much. I also got the recently released Forest Elements (http://www.daz3d.com/forest-elements). This set allows you to build your own forest. The setup scene below shows the ground middle summer set. It is much smaller than the whole forest set, which is also included. I posed my subject on the hill side and positioned the camera. Then I build the forest behind her. I had not problems with DAZ slowing down on this much smaller scene.
I experimented a lot with lighting, and finally settled on a very simple lighting setup. There is one distant light at 100% intensity with ray traces shadows that pointed at subjects side and slightly rear. There is a second spot light at the camera location at 100% intensity, 90 deg spread angle, diffuse only and no shadows.
This lighting arrangement is party based on my outdoor photography experience. Position the subject so the sun is not on their face, then use a fill flash to light up the subject to match the background. I used the diffuse only because I did not want specular highlights on her face and arms from the fill light. I think the specular highlights in the picture look more natural this way. The fill light is also creating something like the ambient light in the forest behind her. Without the fill light the forest would look much darker.
With this very simple lighting setup, render time was 50 min at 800x600 and 1 hr 26 min at 1200x900. These are slow render times, but still tolerable. The memory usage by DAZ was just under 1 GB while rendering this, so you would not need a giant computer to handle this. My processor is I7-3770 at 3.4 GHz, so I think it is a fairly fast processor.
I also tried using another distant light as the fill light, and that worked just fine too, but I don’t think it would work in the real forest set, because trees behind the camera would block the light. A spot light should work in the real forest set.
I tried to use UE2, but the render time went crazy. I canceled most of the renders after hours because there was no point. I don’t think you can use UE2 with even this small forest set.
I’m now going to try some experiments in the real hi-res forest set.

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