Create A Shadow For A Green Screened Character

Hey there!

I am kind of new to visual FX and I don't know how to make a shadow for a green screened character.  I know how to do it when there feet are out of the shot (you just duplicate them, make it black, change the opacity, and set it to the right angle) but I don't know how to do it when they are in the middle of the shot...can anyone do a tutorial on that? Also I can not seem to find a good tutorial for doing 'light wrap'. Thanks!

Plastic Point Productions

Comments

  • tddavis
    tddavis Posts: 5,219 Expert

    @PlasticPProductions @FilmSensei has you covered on this just recently (like just last week :) )

     

    Give a watch to this tutorial:

    https://www.youtube.com/watch?v=7Sy8kWMTC7A

    Certainly opened my eyes.  I hope this is what you are after.

  • JBaymore
    JBaymore Posts: 386 Enthusiast
    edited August 2019

    @PlasticPProductions    I'm pretty new to this stuff also... but have started to get a BASIC grasp on this issue.  I'm sure someone else will post a FAR better description here........ but here goes a BASIC description to get you started in some direction close to reality:

    First off... set up "make composite shot".  Drag in your greenscreen footage over your background image(s).  Key out the background as usual.  Then you have to convert your footage and any background scenery clip(s) into 3-d. This will automatically also create a 3-d camera (that you can move around if you want/need).   Set the property "casts shadows" to on for your greenscreened element.  MAYBE turn off "receives shadows" for your background image ...... it might cause stuff you don't want.

    Then create a new large 3-d plane (to receive the shadow), make it white, set "illuminated" to off", set "receives shadows" to on, set the blend mode to multiply.   Rotate the plane and position it in 3-d space to the place that you want the shadow to appear from the point of view of the active camera.  You can leave the blend set to normal temporarily to help see the white plane as you are positioning it.

    Create a new light.  Set the "creates shadows" property to on. 

    By using the available views in the viewer pane and playing with looking at combination of top, side, and perspective views, get all the elements arranged in 3-d space appropriately to get the shadows where you want them.  This can take some playing around.

    I'm assuming the shadow you want is on the ground under their feet from your comment....so the rotation of that  new "white" (now disappeared) shadow-receiving plane will likely be close to 90 degrees, depending on where you position the camera in 3-d space.  Note that this white plane can end up "penetrating" a background image plane... and then simply disappear (because that part of it is behind that plane from the camera's point of view) ...... so you have to have that background shot well behind the green-screened element enough so that the shadow appears where you want it and doesn't get cut off.

    Position the light relative to the objects so that the angle of the shadows matches the lighting in the background scene.  Again use the views aspect to get positioning right.  Sometimes I've found that with greenscreened 2-d planar objects made into 3-d situations.... this will not work well.  The needed shadow angle makes the shadows of a thin slice of the object creating the shadow.  So the shadow looks like being from a stick.... not a thicker object.

    I hope this gets you started playing with this ........... and any errors here are MINE.

    best,

    .........................john

     

    PS: Look here:  

    and here: 

     

  • Thanks guys! I actually found that video like 20 minutes after it was posted...and sadly It didn't work for me. He had a 3d model, and I have the Express version, which you can't import 3d models into.  I am going to try the shadow thing again. Hopefully I had just done something wrong :)