Ok so this is how you do it.

1. Start poser and pose your figure, prop (etc) as desired.
2. Set the display mode to your desire. Most prople use Hidden Line. Then antialias window and export image.
3. Then render as usual and export image.
4. Open photoshop and both the images.
5. Select the rendered image select all (ctrl + a) then copy (ctrl + c) then paste in the wire frame window. Then close the rendered image. Then the image left over should have the wireframe image as the background and the rendered image on layer 1. It should look like this.
6. Then goto Layer > Add Layer Mask > Reveal All
7. Then make the foreground colour black and the background colour white. or visa versa but they have to be black or white and not white white or black black. Then select the gradient tool and draw a gradient across the image
8. If you did it right your image should look like this.

If you have any problems.