I'l make a suggestion, take it or leave it......

Render out a scene in your best chiaroscuro style with "HDRI Output" selected in render options. Then, save out the result as format "openEXR."

Take that file to your buddy with PS CS2/3 and open it. Photoshop will recognize the format and limit your editing choices to those possible in 32-bit mode. The two most important are:

Channel Mixer
Exposure.

You have six or seven total sliders under those two functions. I think you've be very interested to see the power you can bring to bear. It takes some practice to determine what factors are being driven, but you'll catch on.

When you get the look you want, you "tone balance" the image and export it in an  8-bit format that is optimized for todays 'lame' monitors. Some day you'l leave it in 32-bit when our monitors have jumped up a generation or two.

This is not "magic" since you are editing and viewing on a current-gen monitor, but what you get is roughly a "brightness/contrast" editor on steroids.

One of the reasons I like this workflow is that it specifically reduces the endless tweaking of lights and shadows in Poser. I get the render "in the general vicinity" of light/dark/contrast I want, then take it into post as openEXR to bring it home.

NOTE: I'd suggest not selecting gamma correction in the Poser Render. Gamma correction is included in the above 32-bit editing workflow above and you have more control and instant feedback in PS.

::::: Opera :::::