Quote - How do you put in a background so you don't get a shadow on it? 

Fog would be cool! How would I add that? In postwork?

Thanks for all the suggestions

You can always just add your background in your graphic program.

What I do with all of my renders if they are going to have a background image:

1.  Set up your scene with everything you want including the background. Add the background using the technique in step #2

2.  Add a single sided square to your scene.  This is found in the props folder of the Poser runtime folder.  Go to the material room and right click in the working area. PIck "New Node", "2D_Image Node" and then "Image_Map".  Browse to the background you want to use. Plug that node into the 1st and 3rd channels.    You have just made your background into a prop so that it will interact with your scene including picking up the light in your scene and it allows you to turn your background and move it around unlike when you "import" it.

Now go back to the Pose Room and use the X Y Z scale files to make the square the same dimensions as your background image IE: 1024 x 768  or whatever it might be.  Then use the Z Trans and Scale to push back the square so that it's behind the scene and then Scale it up to whatever you need so that it works as a background for you. 

3.  Use the parameter dial options to make your single sided square invisible.  You want to render the scene without a background.

4.  Set your render settings so that  you are  rendering your scene over black.  I found that if I used any other colour that  there was a 1 pixel border of that background colour around all of the edges, and very noticable if I later wanted to put that image on a dark background.

5. Save your render as a .png file.

6. Now go back into the Pose Room. Make your single sided square visible again. Hide everything else in the scene.

7. Render the prop / background.  Save as a .png when done.

8.  Open both renders in your graphic program.  Paste the background into your scene image and drag it to the bottom.  The background now has the same lighting as the rest of the scene, but it doesn't have any shadows.

As far as Fog goes, you can read this thread to find out some techiques and ways to add it:

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2502535

Here are some tutorials that show you how to add fog in post work:

http://www.daz3d.com/i.x/tutorial/tutorial/-/?id=711

http://www.daz3d.com/i.x/tutorial/tutorial/-/?id=1036

http://www.daz3d.com/i.x/tutorial/tutorial/-/?id=1681

http://www.daz3d.com/i.x/tutorial/tutorial/-/?id=1744

http://www.daz3d.com/i.x/tutorial/tutorial/-/?id=1750

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