Ray tracing high quality still shots

Dear UE community

I have been fooling around with raytracing for a while and I was thinking about how to get it working to produce high quality still images.
I want to tell unreal to calculate GI accumulatively and keep it up untill i have crystal clear image, like one can do with unbiased renderers like Corona.
is that possible?

thank you!

take a look at path tracing mabe !