raytracing GI and emissive material

as you can see the GI doesn't change when I increase the intensity of the emission.
is there a setting somewhere ?

 

As I understand it emissive implementation done as a part of Global Illumination diffuse bounced light (light bounces from emissive surfaces treated like it's bounced from diffuse surfaces, but with boosted brightness) - this makes it's rendering free and shadows from it also free, but limitations are severe:
1)Emissive rays brightness range is limited to a bounced light brightness range - you can increase it 10 times in Global Illumination settings ("Clamp value" - from default "1" to maximum "10") but that is it, nowhere nearly enough for day scenes (reducing sun & sky brightness 100/1000 times and tweaking postprocessing exposure may help). Also, high clamp values gives much more noise to filter ("fireflies/hot pixels").
2)In fast "Tier 1" ray tracing mode there is only one bounce for light rays and because our emissive surfaces made as bounced & boosted light from diffuse they already using one bounce. So, emissive surfaces lighting doesn't produce secondary light bounces in Tier 1. This makes many (too many!) situations like ceiling lamp done via emissive texture cast light on the floor but ceiling itself stays completely dark because there is no bounced light from the floor.
3)Emissive surfaces themselves are reflected in ray traced reflections, but lighting from emissive surfaces not appears in reflections.

Working with emissive lights is a challenge, solutions are possible but it's hard to catch that small area between many settings and compromises were all looks at least not that bad.

 

so tier2 should provide emissive GI?

anyway the entire look just broken, raytrace is preview I think.

 

Both tier 1 and 2 have same emissive implementation with same problems, except in Tier 2 you can have more than one bounce for Global illumination and this way emissive lights can have bounced light. How it looks in Tier 1 with "Clamp value" set to "10":

 

gorgeous
i am definitely not getting that look
care to share a screenshot of your setting?

 

Here they are:

 

i'm not seeing all these options on mine, also show me your material



NB: pathtracing looks amazing but still no emissive

 

getting a bit of emissivness in raytrace gi with clamp at 10
large nits value of emissive yield very little illum as you can see

 

As I see on your screenshots with settings there is a potential trouble with using "Visual environment" and "HDRi sky" settings inside post-processing volume (better delete them from there and create separate "Sky and fog" volume):

About my settings - already messed up since screenshots were taken, but emissive brightness was around 1000. It's actually not about this value but about "Exposure" -> "Fixed exposure" setting & reduced sky and directional light brightness accordingly. After yesterday experiments I have good visuals for emissive lights while using those settings:
1)In post processing: "Exposure" -> "Fixed exposure" is "-5.76" ("Global illumination" -> "Clamp Value" is "10" of course).
2)Directional light intensity (lux): "0.1"
3)in "Sky and fog" volume "Physically based sky" exposure is "2.3" (it's mostly depends on the Directional light brightness).
With those settings my emissive material has "Emission intensity" only "0.3" and this tiny value gives same results as on my first screenshot in this thread, just because "Exposure" -> "Fixed exposure" settings.