Light Artefacts

[WimOos]

I have this huge space, lit by sun and sky and some recessed lights in the ceiling. I have animated a camera with 5 still views in the space. The light chache is calculated with fly-through mode and the irr map with incremental during a pre-render at half resolution.
The other 4 images are fine, just this one have these light patterns.
Attached is the render.
Anyone have any ideas on how to get rid of them?

Settings as follow:
Irr Map, medium preset, HSph=50, interp=20
Light cache, subd=3500,size=0.02 (fly-through for the 5 views)

[vlado]

What are the bright streaks at these areas (lights, or windows, or self-illuminated materials)?

Best regards,
Vlado

[WimOos]

Its meshes booleaned into the ceiling to get 'n long cut in the ceiling. The inside top edge has a vraylight material with low settings and then also in each cut are 2 long vraylights set to invisible. The vraylights do not touch any geometry.

[vlado]

Ok; does it change if you switch to the "High" irradiance map preset for the final rendering (it changes some of the thresholds used to interpolate the irradiance map)?

Best regards,
Vlado

[WimOos]

Perfect! Thank you Vlado, that did the trick! All artefacts are gone now and rendering looks perfect!

Thank you!