Background matching and camera matching assist in compositing virtual 3D model into real background photo.
 

Preview wireframe with background image:

Final image:

Model: Courtesy of Ran Sarfati

To view wireframe with background image in preview window, open View Options dialog, choose Draw and check Background.

Tip: Preview window and final image should have the same aspect ratio

To set preview window size according to final image size, click Image Aspect ratio, click OK to close Image Aspect ratio dialog, and Click OK or Apply to apply new size.
Check Keep Aspect ratio to avoid aspect ratio change when resizing window.