How to prevent color casting?

[pietrop]

I'm trying to create a green-screen material so I can do some fast tests on the final rendered image using Photoshop.
I created a green material and rendered the image but the material casts a lot of green (color) in the scene. Is there a way to prevent this behaviour?
Thanks

[ntxdave]

Would it be better to export the model with a transparent background and then import that into Photoshop.

[pietrop]

I forgot to mention that the scene is indoor with skyportals, so the transparent background doesn't apply to my case.
Is there a way to solve this?
Thanks

[Fletch]

reduce the saturation on the green color to 70%, it's not "obeying" physical laws.

Remember you can render a technical setting called "Diffuse Texture Pass" and it will render just flat colors. You render that at 2x the size of your final rendering, in this pass your green will be flat and easy to select in Photoshop. When you make the selection on the 2x sized result, then create your alpha mask for the layer. Then resize the image to match the rendering, and the alpha mask will be smooth and high quality.

[pietrop]

Thanks Fletch, this is exactly what I was looking for