• Adobe After Effects

  Keying but keeping the shadow

  Posted by Kate Koyama on June 25, 2012 at 7:45 pm

  Hello there!

  So I want to key the video but still keep the shadow.
  We’re doing a video where the background changes but the objects sitting on the background stays. Since the object is sitting on the green screen itself it projects a shadow. Now we want to keep the shadow to give it a more realistic look.

  But everytime I key it out the shadow gets a lot of noise! A LOT!

  Now I want to avoid turning the video in #D and applying lights, because it’ll make it even larger… so is there a good way to key out the green screen but keep the shadows that are being reflected on it without the noise??

  Darby Edelen replied 14 years ago 4 Members · 4 Replies
• 4 Replies

• 

  Kevin Camp

  June 25, 2012 at 8:08 pm

  if you are using keylight, setting the screen matte>replace method from soft color to hard color may help. it often helps to reduce noise that keylight seems to produce with its despill process, which might be what’s happening here.

  you could also try setting the view to intermediate result (no despill process) and then using the remove color matting effect to try and remove the green from the shadow that way.

  also, andrew devis has a series of tutorials that cover multilayer keying in the tutorials section that may be useful here…

  Kevin Camp
  Senior Designer
  KCPQ, KMYQ & KRCW
• 

  Nevin Styre

  June 25, 2012 at 9:09 pm

  I myself would probably fake it.
  Take the already keyed layer(with shadow keyed out), duplicate it, add a fill effect(black) to bottom of the 2 duplicated layers, lower the layer opacity & reposition/transform the layer to look like the shadow, add a blur if necessary. To go even further use a radial ramp instead of a fill, use a black/grey gradient, and use transparency modes(darken, multiply, etc.) to give the shadow some falloff… experiment with duplicating the shadow layer & combining different transparency modes & opacity values to fine tune the effect.
• 

  Kate Koyama

  June 25, 2012 at 9:28 pm

  thank you for the link!!
• 

  Darby Edelen

  June 26, 2012 at 2:58 am

  You could try using some color correction to produce a usable shadow.

  I’d start by duplicating the green screen footage and applying a Hue/Saturation effect to it. Desaturate the greens so that your shadow is a dark gray spot in a large gray area, then use a Levels effect to push the area surrounding the shadow into white. Set the blend mode of the layer to Multiply and place it below your keyed footage.

  Depending on how evenly lit your green screen was you may need to use a mask around the shadow area. Also, try to reduce the amount of shadow that comes through on the key.

  Also try tweaking your Despill Bias.

  Darby Edelen

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