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Do any of you good people know how I might create an underwater caustics effect in OB?

I found something specific to C4D the other day that shows a caustics option within Octane Light settings. Is there an equivalent method?

Hi!

Could you please post the link to the Cinema 4D example?

Thanks.

linograndiotoy wrote:Hi!

Could you please post the link to the Cinema 4D example?

Thanks.

Hi Lino,

https://youtu.be/oFWdNHmcmIY

Just realised it's in Physical, not Octane

...but the question still stands

Found some good pointers here from from bepeg4d and FAZ:

https://render.otoy.com/forum/viewtopic.php?f=30&t=63407&p=323785&hilit=caustics#p324459

...but it's a little disjointed i.e. I can't find 'specular depth' in the PT kernel.

I've had the most success with PMC kernel in terms of noise, but wonder if there's a more efficient way. 5K samples plus Denoiser rules animation out for me...

Also, depending on what you're doing, it's still usually a lot faster and easier to fake it with a gobo.

Whispermode wrote:Do any of you good people know how I might create an underwater caustics effect in OB?

I found something specific to C4D the other day that shows a caustics option within Octane Light settings. Is there an equivalent method?

Could be doable with PMC kernel but render times will be very long. Better fake it as frankmci said.

frankmci wrote:Also, depending on what you're doing, it's still usually a lot faster and easier to fake it with a gobo.

Thanks, frankmci - I'm only just learning about gobos.

So how would you approach it in an animation? An image sequence of an underwater caustic pattern?

Whispermode wrote:

frankmci wrote:Also, depending on what you're doing, it's still usually a lot faster and easier to fake it with a gobo.

Thanks, frankmci - I'm only just learning about gobos.

So how would you approach it in an animation? An image sequence of an underwater caustic pattern?

Yes, I'd probably use an image sequence. You can do it with an animated shader in Octane, but for me that tends to be very finicky, when I can knock out a sequence in After Effects in a few minutes. A sequence will also render faster, since Octane doesn't have to covert the shader to a bitmap for every frame each time.

The gobo rout will give you both caustics and nice god-rays without a lot of tweaking, and can render pretty fast without a crazy number of samples.

frankmci wrote:

Whispermode wrote:

frankmci wrote:Also, depending on what you're doing, it's still usually a lot faster and easier to fake it with a gobo.

Thanks, frankmci - I'm only just learning about gobos.

So how would you approach it in an animation? An image sequence of an underwater caustic pattern?

Yes, I'd probably use an image sequence. You can do it with an animated shader in Octane, but for me that tends to be very finicky, when I can knock out a sequence in After Effects in a few minutes. A sequence will also render faster, since Octane doesn't have to covert the shader to a bitmap for every frame each time.

The gobo rout will give you both caustics and nice god-rays without a lot of tweaking, and can render pretty fast without a crazy number of samples.

OK, I'm going to give this a try. I really appreciate your help - thanks.

I would totally use an animated Octane Procedural texture to simulate this.

I included the scene i made. Turn on the preview and hit play.

You can use this as a mask so you can add animated caustics where needed.

I hope this helps.