Blured Mirror Reflection

Hello. I'm having a puzzling question about [MirrorReflection2.cs] now.

http://wiki.unity3d.com/index.php?title=MirrorReflection2


I revisioned this script to blur render texture (reflection)
with the use of Graphics.Blit before SetTexture to _ReflectionTex, and it works fine.


[MirrorReflection.cs]

Code (csharp):

1.  
2. //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3. //---Add Blur---
4. Material mat2 = new Material(blurShader);
5. RenderTexture buffer = RenderTexture.GetTemporary(m_TextureSize, m_TextureSize, 16, RenderTextureFormat.ARGBFloat);
6.  
7. mat2.SetFloat("_Blur", blurAmount);
8.  
9. Graphics.Blit(m_ReflectionTexture, buffer, mat2, 0);    //  Horizontal Blur
10. Graphics.Blit(buffer, m_ReflectionTexture, mat2, 1);    //  Vertical Blur
11.  
12. RenderTexture.ReleaseTemporary(buffer);
13. //------
14.  
15. foreach(Material mat in materials){
16.     if(mat.HasProperty("_ReflectionTex")){
17.         mat.SetTexture("_ReflectionTex", m_ReflectionTexture);
18.     }
19. }
20. //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21.  

However, the lighting of the scene will be strange for some reason.:-|


[with Graphics.Blit] strange


[comment out Graphics.Blit] correct (original code)


I want to blur RenderTexture but when I tried it with the Graphics.Blit I wrote,
I don't know why my lighting changes as well. I'm stuck...