This topic is veeery old, bud I find myself having the same problem in v-ray 3.4
And I have a beast of a machine - threadripper 1950x + 32 gb RAM + GTX 1080Ti.
No luck with xeon at work.
Any new info on the solution?
The other factor in this is if you use the physical camera and use realistic values for night-time photography (low shutter speed, large aperture, high iso) you will be able to use more realistic lumen values.
Seems like it may be a bug. Do you have any refraction on that glass material? Have you tried to use a glass material from the Chaos website to see if it creates the same issue?
