Reflections From Box / Spherical Captures Appears Low Res at Low-Mid Roughness Values

Hi everyone,

so I’ve noticed something when it comes to rendering reflections on rougher materials. It appears that increasing the roughness of a material seems to make the overall reflection capture image more low res and slightly blurry. (see images below)

I believe in OpenGL to fake levels of roughness one would create MIPs of the captured texture and then apply some sort of blur on top. However, I was wondering if this is what is happening here and if so how can I improve the look / blur and make it seem less blocky and more smooth especially at low-mid roughness levels.

Just also wanted to add that I have set the maximum resolution of reflection captures to 1024 in the project settings.

I have attached two images… one with roughness at 0 and one with roughness at 0.2 as soon as it hit higher levels of roughness the highlights get more blocky / low res.

Thank you in advance for your help!