Thanks!
detail tracing was checked already. The glittering problem was there already when the cards were on the default value of 12. The secondary bounces are just sort of glittering as I am moving around. I tried even to change the material to basic, happens in entire scene in some places and looks almos like some postproduction effect. Checked some tutorials on more detailed interiors and never seen this issue.
here is the vizualization:
even I more simplified the scene, the problem is same, leaks visible from the outside:
just realized when I change the shadow map method to non-beta the problem is solved, but as a noob, not sure yet what other good stuff I am loosing with this change:
and now realized there were shadow maps on the template light I changed to raytraced and all is ok. Is it good idea to use rt shadows for this case in UE? Stupid question I know, but I dont have much experience vith realtime…