How can I create a 3 dimensional gray paper photo background

[Koula]

Hello

I have a photo of three people. One is standing and two are sitting on the floor. I need to remove them from the actual photographic background and place them onto a new simulated gray paper background. My main problem is: How do I make the fore and backgrounds look realistically 3d without having a seam adjoining floor to wall? Is there a dismap?

Thanks in advance
Cheers

 

[Chester]

?? [confused]

use the zoom tool and work in detail... there are no click-and-ready buttons for this...

 

[wbiss]

Koula, if you mean that you want a "seamless" backdrop for your subject matter, but you want to create the impression of 'dimension', I would rely on the use of:

a) highlights
b) shadows
c) perspective

Here's a small example of what I mean.

Notice that the 'window light' suggests a wall and where the light bends, it suggests a floor. Also, note the shadows. The standing boy's shadow bends where it meets the imaginary wall.