Hi all,
I’m trying to read all the relevant posts on the this subject. As you can see from my Youtube channel,(user/tetanoisee) I’ve been doing ue4 / raytrace tests since the dev rendering stage, and “rawalance” summarizes all the problems I’ve encountered.
in my opinion, the current consumer GPUs are not enough to use all the features of raytrace for "real time/ 60fps ". I don’t think this is related to the software side of the problem. I think it’s all about hardware power. If you look at the videos on my YouTube channel, even at simple levels, all raytrace features are enabled and sample values are increased, even rtx2080ti suffers from fps)
Of course, it is not surprising that we use the game engine as the primary point of view in terms of performance/quality. however, existing GPUs seem inadequate. (perhaps the algorithms can be strengthened as the screenspace for real-time performance, but this time conflicts with the purpose of use because the accuracy of raytrace is lost)
like other users, I tried UE4 in different usage scenarios. I focused more on the export sequencer animation. All the features in my 4k 60 fps export attempt still didn’t work. (usually with high sample values, crash or noisy export)
in the light of all these results;
- Existing consumer GPUs are insufficient in the “Real Time” section for this Raytrace/ dxr technology. (I’m not just talking about reflection; I’m talking about performance when using all the gi, ao, reflection, refraction, and shadow features on the raytrace.)
We should be able to use the export sequencer effectively for raytrace. I think this section is hardware independent. hopefully version 4.23 can improve this section (crash and noise problem in high sample)
-One of the biggest problems I’ve seen in my tests is the shadow part of translucent objects (I’m not talking about translucent shadow, I’m talking about whether shadow is active or passive.huge difference on interior lighting.)
-After many tests, I can easily say that there are differences between 4.22 and 4.23 about RTGI, lights, foliage lighting and denoiser.
same level migrated from 4.22.3 to 4.23 P8 here is results ;
(low rtgi samples)
with denoiser :ue4 (4.22.3 vs 4.23 P8) dxr compare - Imgsli
without denoiser : ue4 (4.22.3 vs 4.23 P8) dxr compare - Imgsli
I don’t know what’s the difference from the technical point of view but;
i think …
-rtgi works more accurately at 4.22.3
-denoiser works better at 4.23 p8
-I don’t know if -foliage was supported in 4.22.3?
-Light falloff values are not the same. (Is it normal to have so much difference that I migrate to the same level?)
-the two-sided processing of some objects has changed.
In the forum, I would like to discuss raytrace as own section … where do I sign? 
I would like to congratulate the whole team, especially the juan canada. I’ve been doing 3D visualization for 20 years and it’s really exciting to experience the point where technology comes from.
I’m sorry about my bad English.