Temporarily turn off fresnel effects (UE4)

Hi everyone,

I’m new to Unreal Engine 4, so sorry if this may sound like a silly question.

Some assets in my environment have fresnel effects, configured by the Fresnel node found under Utility. I’d like to temporarily disable all of them to take a screenshot, ideally without having to detect and iterate over each one of the materials. I tried disabling ShowFlags one by one but none of them seems to impact the Fresnel node. Would you have an idea on how to do it?