Recently, I purchased a Tiffen Black Pro Mist which adds halation to highlights via diffusion. I read online that diffusion filters do not add data as the entirety of the effect can be recreated in post with more flexibility. It appears that the size of the halation is proportional to the intensity of the light source. What's the actual physics of diffusion filters? Thanks in advance.

[![diffusion 1](https://i.stack.imgur.com/GRiQS.jpg)](https://i.stack.imgur.com/GRiQS.jpg)

[![enter image description here](https://i.stack.imgur.com/qz5WZ.jpg)](https://i.stack.imgur.com/qz5WZ.jpg)

[![enter image description here](https://i.stack.imgur.com/wHjqh.jpg)](https://i.stack.imgur.com/wHjqh.jpg)