AI light is still broken Tweet

[coilbook]

Hi Paride,
There is still a problem with AI light. Render times go from 2 min 25 sec to round 12 min per frame with no visible improvement.

Can you report this to the developers? I sent many scenes about it and I can send more if you want me too. I just don't see how AI light helps us when it makes render time 5 times slower

Thanks

[paride4331]

Hi coilbook,
I made some test, I'm sure if it depends on your emitters setting or any issue using emitters with Forest Pro.
I tryed using many emitters but not istanced using Forest Pro, AILight seems work well.
Could you try instacing the emitters but not attached into geometry?
Regards
Paride

[coilbook]

Hi coilbook,
I made some test, I'm sure if it depends on your emitters setting or any issue using emitters with Forest Pro.
I tryed using many emitters but not istanced using Forest Pro, AILight seems work well.
Could you try instacing the emitters but not attached into geometry?
Regards
Paride

Thanks. I will send you another scene soon

[tcheng00]

I built a highway scene and the road lamps are all using emission lights with 1 sample. The lamps are also instanced along the highway. I noticed that using AI Light is doubling my render times. Any idea how this works? If the render times are getting longer, isn’t AI lights optimization not working?

[frankmci]

I built a highway scene and the road lamps are all using emission lights with 1 sample. The lamps are also instanced along the highway. I noticed that using AI Light is doubling my render times. Any idea how this works? If the render times are getting longer, isn’t AI lights optimization not working?

If the only thing changing is AI lights "on" or "off", then yes, the render can take longer when on, although double seems a bit high. However, the idea is that with AI Lights enabled, you can significantly reduce other sampling settings and still get low noise levels, with overall faster results. You will probably see what looks like lower illumination levels with AI Lights enabled, also, since the rays from each light source are being more closely constrained. It's not a magic bullet; you'll need to tweak your scene and lights to take proper advantage of it.

I suggest that you try experimenting with extremely low Max Sampling settings (like Path Tracing, Max Samples: 8 or 16) and de-noising turned off in a very simple scene to get a feel for what's really happening. Go back and forth and use your A/B comparison as you fool around. Once you have a feel for it, turn up the Max Samples just to the point where your AI enabled lights look good. Then try it with them off. Now see how much higher you have to turn up your Max Samples to get the light noise under control again. The AI Enabled version will most likely render a lot faster with significantly lower Max Samples settings.

[tcheng00]

thanks, I'll give this a go, but I think to be truly AI, I think this shouldn't even be an option and the system should be intelligent enough to figure out if this is benefitting the final render time or not and self optimizing behind the scenes. Giving user options is great, but each option need a render test and the more options you give the user, the more they have to test to find the optimal settings. I think this sorta defeats the purpose of saving time in render by increasing user test time.

[frankmci]

Obviously, this is not truly AI, any more than IBM's Watson winning Jeopardy is truly AI. "Machine learning," "AI", "Deep Learning," they are all still just techno babel for very cleverly optimized algorithms. This light sampling optimization algorithm can't make the ultimate aesthetic decisions; those are up to you. This is just one tool in your toolbox. The AI light has one fairly narrow region of influence, and predicting exactly how that is going to affect the rest of the scene, and what aesthetic and technical choices should be made based on it is far beyond the scope of this tool. Making those choices is part of what you are paid for.

No, it does not defeat the purpose if you know your tools. This tool can make your images look good with much less effort and save huge amounts of render time, but as with any art or craft, you need to know and understand your tools to use them effectively. That takes practice and experience. Again, that's part of what you are paid for.

[tcheng00]

With all due respect, I don't agree with that. They pay me to produce the art with a very quick turn around. The quicker the turn around for the same artwork, the more value I offer. If I can do a job spending less time tweaking render options and more time making my composition, texture, or geometry better, I rather spend the time making my art better. Besides, what company wants to pay someone to sit there testing out a bunch of render settings when they don't have too, especially as the competition is simplifying and making things easier not harder.

[paride4331]

I built a highway scene and the road lamps are all using emission lights with 1 sample. The lamps are also instanced along the highway. I noticed that using AI Light is doubling my render times. Any idea how this works? If the render times are getting longer, isn’t AI lights optimization not working?

Hi tcheng00,
tray to take a look at here:
https://render.otoy.com/forum/viewtopic.php?f=27&t=73990&p=377985&hilit=+bulb#p377985
https://render.otoy.com/forum/viewtopic.php?f=27&t=60648&p=310376&hilit=+bulb#p310376
Regards
Paride