Bin Chen 2008
I have added support for depth of field. Depth of field is useful to get rid of distracting background and add realism to the rendered image. It seems to be very good when I tried them on the diffuse lotus. However, for the final scene with glowing lotus flowers, it seems that both flowers are too important to be blurred out since each one has some detail that I wish to show in the image. In addition, depth of field does not seem to work very well with bloom in my scene, so in the final image, I did not use this feature (or it could be understood as the aperture size is so small that the blur is not detectable).
Blurring the back and front lotus:
Depth of field test image: