corona lights with directionality going black when seen through refractive glass

[Rhodesy]

As shown in the screen grab image, the standard corona light turns black when seen through glass with refraction activated (not thin). The light has a directionality of 0.55. If it gets reduced to 0.4 the light can be seen fine. Anything with directionality over 0.5 renders black. Numbers lower than 0.5 do also dim in appearance so it would be good for directionality to have no bearing on the appearance of the visible light source.

Thanks
Rob

[TomG]

The "prevent black appearance" doesn't work in refraction at the moment, unfortunately, a known issue. The directionality means that no light from the light source actually reaches the camera, so this is physically realistic (just like if being viewed directly), but often not what people expect, which is why the "Prevent black appearance" was introduced - but as noted, it doesn't work in reflectiion or refraction.

The solution for now would be to create two objects - the light source that emits light, but is made invisible to the camera; and a light source that will be visible to the camera but doesn't emit light (e.g. geometry with CoronaLightMtl with Emit Light unchecked).

[Rhodesy]

Thanks Tom, makes sense.

[FrostKiwi]

Alternatively use the Rayswitch Material and skip having two objects. (Corona light rectangle is the same as a plane with light material, when the plane has only one face)
For GI have the Light material with directionality and for everything else have a copy of the light material without directionality