VFX Artist Explains the HARDEST Visual Effect to Make

THIS EPISODE ► Wren explains the most scientifically difficult visual effect to pull off - light caustics. But what exactly makes caustics so difficult to simulate?

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[SirPembertonS.Crevalius]

I always loved seeing the ins and outs of VFX, it's a perfect example of "if you do things right, people won't be sure you've done anything at all."

[carlosnascimento]

"Real life runs constantly in real time without ever crashing."
Well, I would certainly hope so.
Great video Wren.

[teepeepictures]

The history of long hair in animated movies. Simulating hair has been such an interesting subject. I think it would make a pretty good video.

[jgust]

Just watched avatar the way of water and it’s definitely simulated. The light patterns changes accurately when a creature is disturbing the water surface. It’s crazy how good it looks.

[crazybobby]

Imagine that the reason for "Avatar: The Way of Water" to have taken so many years to be released was due to the caustics finally finished rendering.

[The_Razielim]

Man I missed Wren's deep-dives into very specific topics.

I enjoy most of the content on this channel, but those hit particularly hard for me since he usually does either a science-y topic, or something crazy and obsessive about a sci-fi franchise... in either case, I love the effort you (Wren + the whole team involved) put into these vids.

[danelyman]

Wren is honestly a great educator. Has a passionate energy, knowledgeable background, and ability to simplify complicated ideas. He really could have his own education channel and I bet it'd be huge!

[prodigystake]

omg I cant believe mark is actually doing normal stuff for the channel this is so cool. this just made corridor crew 10x better.

[mrandersen]

Wow I can't believe wren was able to speak under water so clearly!!! Fantastic job!

[vanshgarg]

Wren : finds an amazing shot
Wren a few minutes later: realizes the shot was simpler than imagined
Also Wren : fuck it, I wanna try the hard way and see it's worth it
And that's why we love this channel

[branbroken]

When you consider if someone were to actually run that 11 year render, by the time it finishes you would probably be able to run an equivalent render in an hour with the advances in both hardware and render algorithms, probably also with some sort of AI enhancement thrown in.

[TheBrownieSundownHD]

These Wren videos are some of the highest quality videos out there. His understanding and ability to explain these concepts is so unreal. Great stuff!

[Insertnamesz]

I love Wren's solo vids. Learnt a lot once again. Keep it up.

[overanimated]

it's a shame to come back to a video i used to enjoy, now knowing this company is so comfortable with art theft and is even complicit in it.

[xodiaq]

The randomness on the simulated caustics is why they feel better to my eye, the gobo is very cyclical. If it was an isolated beauty shot, the simulated will make a HUGE difference, but in the Dino scene it’s probably not worth it.
Really cool topic!

[CaptainOblivion]

I think the main case where simulated caustics for an underwater shot would be more notably different than the gobo option, is when the thing catching the caustics is very close to the surface of the water. The parts of the dinosaur that are right up against the water would catch very different caustics than the parts further away, not just in brightness but in sharpness as well. If you move the dinosaur further underwater, the difference between the close parts and the far parts becomes less significant, and the result looks a lot more like the gobo.

[jasonchiu]

Wren: "It will take 11 years to render it!"
AI: Two more papers down the line. Take it or leave it.

[StewartFletcher]

That montage of all the glass renders was honestly one of the most beautiful things I've seen

[McCallahanIndustries]

Wren emerging from the deep is a callback to Sync when the main character wakes up in the ocean.

[_Prince_Of_Darkness]

As far as I'm concerned I saw the trailer of Avatar the way of water multiple times and each time I caught some new details but talking about Caustics, yes they were both a mixture of original shots under water and perfect cgi because one can clearly see the rays of light in the trailer but that doesn't happen in real life and the Caustics get dull as depth increases also the clarity of water is the biggest factor in play here, cleaner the water more crisp are the Caustics