I'm working in a scene with a semi-transparent material (think translucent HDPE / cloudy PC) and found that turning on focused caustics gives a more realistic expression of the semi-transparent material, however I am getting considerable blotchiness and light blobs throughout my scene. I can't post my most readily available screenshot due to sensitive material, however I assumed this issue was pretty common and someone might know a good fix.
Settings as follows:
Ray bounces: 8
Shadow quality: 1
Rendering quality: Max Time @ 4 hours
Global Ill: ON
Ground shadows: ON
Focused caustics: ON
Cheers