Ocean close up quality hack?

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Hello everybody,

I come with a challenge. I'm working on a production with a lot of ocean in it and, sometimes, we get rally close to the water. The thing is, the ocean tools are great when you are far from it, but when you get close, about 5 meters or so, it start showing artifacts (please check attached image).

Now, I know why this happens and the option I have to fix it, namely increasing the Resolution Exponent. but when I go over 12, things start getting unbearably slow and render times pass the 2 hours per frame mark.

That said, I am willing to put up with more render time if I get the quality I need, but it's hard since the displacement maps become absurdly big, causing resources like RAM to evaporate and Houdini to crash.

So the question becomes, does any of you would share a trick I can use for this situation?

Any suggestions?

Kindly appreciated in advance.

Attachments:
oceanQuality.PNG (1.3 MB)

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You should increase the refractive index of the ocean surface,And add volume to your ocean。
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Van Darkholme
You should increase the refractive index of the ocean surface,And add volume to your ocean。

I will surely give it a try, thanks!
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you can also add a secondary noise into the bump in the shader, to add those micro details.
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Heileif
you can also add a secondary noise into the bump in the shader, to add those micro details.
Wow… never thought of that. Thank you!
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So, now the project has ended and it's time for some conclusions.

The close-up quality situation… there seem to be no way around this. Yes, I could use a small ocean in my efforts to lighten the load, but if then the camera moves and looks at the horizon, that laves me without many options but to use a large ocean and, the way both work are mostly the same anyway. There is no way around a brutally big displacement map (16k, sometimes more).

How did I went around this:
1.- Play with the scale: Instead of going 1:1, I set the scale of my shot to be 10:1 (created a null with the scale change and applied it to everything except the ocean), this way, instead of the camera being 1.5 meters above the ocean surface, it was 15 meters high. This allowed me to get away with a resolution exponent of 12 (max).
2.- Motion blur: I made a quick vector velocity calculator inside the shader to get me a vector velocity pass. This way I could get away with lower quality (faster renders) in shots were the camera moves fast (which was all of them except for two).
3.- Speed up renders by bypassing ocean interior (on some shots), taking the shading quality multiplier down to 0.5 (as lowest value depending on the shot), and max ray samples to 4 (as lowest value depending on the shot).
4.- Try the suggestions given by Van Darkholme and Heileif. Although, in some shots they worked wonders, on others just added time to my renders without adding any extra juice to the shot, but that is to be expected. THANK YOU GUYS!

I rendered C, Pz, N, Dl, Il, vel image planes and give all that to the compo guy. He was able to work his magic and the final result is quite pleasing.

Cheers!
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