Cant get caustics from top view through water

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microvswind
Posts: 4
Joined: Tue Nov 18, 2025 1:49 am

Cant get caustics from top view through water

Post by microvswind »

Cant get caustics from top view through water.
I have watched a lot tutor on youtube and tried a lot with help of discord,but no luck.
My goal is got sharp caustics from top view though water surface.the pool is 2X2X.5 m
Image
Image
https://mega.nz/file/R2c1RD5R#JNMOXA9a9 ... 6Xnrj-JuUU
https://mega.nz/file/Rz0iBR7b#SGRIA4FkE ... t5Ov9BQnok
epilectrolytics
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Joined: Thu Oct 04, 2018 6:06 am

Re: Cant get caustics from top view through water

Post by epilectrolytics »

This is strange, when I open your file with Blender 4.5 and LuxCore 2.10 on my MacBook and hit render I get caustics immediately :?
What hard- and software do you use?

Still I made another file with some changes:
- switch to BiDir with 4/4 Bounces only because Hybrid engine does not work with skylight caustics efficiently
- use Metropolis sampler and uniform light strategy
- adjust caustic cache settings
- 1 min sample time is too short, use 256 samples + denoiser instead
- attach sky to sun light in light settings
- use scaled down ocean instead of displace modifier, add subdivision after displacement (and smooth shading)
- pimp up the glass material with blue volume and a metal surface component to catch the sun reflections
screenshot.jpg
Attachments
Cau3.blend.zip
(118.19 KiB) Downloaded 15 times
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JaAlVir657
Posts: 12
Joined: Thu Jul 10, 2025 2:27 pm
Location: Switzerland

Re: Cant get caustics from top view through water

Post by JaAlVir657 »

Hello,
I confirm what epilectrolytics said !

Your file with a render time of 600 [s] :
Image

I would add one point : you need to check your 3D objects (normals, triangles, and disjoint faces; e.g., the letters used "raw") to avoid the kind of defect that appears as indicated by the pink arrows.

File similar to epilectrolytics's "Cau3.blend" but with the letters corrected :
Image

@epilectrolytics, thanks for sharing your experiences !
microvswind
Posts: 4
Joined: Tue Nov 18, 2025 1:49 am

Re: Cant get caustics from top view through water

Post by microvswind »

epilectrolytics wrote: Tue Nov 25, 2025 7:35 pm This is strange, when I open your file with Blender 4.5 and LuxCore 2.10 on my MacBook and hit render I get caustics immediately :?
What hard- and software do you use?

Still I made another file with some changes:
- switch to BiDir with 4/4 Bounces only because Hybrid engine does not work with skylight caustics efficiently
- use Metropolis sampler and uniform light strategy
- adjust caustic cache settings
- 1 min sample time is too short, use 256 samples + denoiser instead
- attach sky to sun light in light settings
- use scaled down ocean instead of displace modifier, add subdivision after displacement (and smooth shading)
- pimp up the glass material with blue volume and a metal surface component to catch the sun reflections
screenshot.jpg
Thx so much for the help.
Hardware:4060 laptop 8G VRAM + 16G RAM
Software: blender 4.5 alpha + luxcore blender 2.10.2
microvswind
Posts: 4
Joined: Tue Nov 18, 2025 1:49 am

Re: Cant get caustics from top view through water

Post by microvswind »

@JaAlVir657
thx for the tip.will test
microvswind
Posts: 4
Joined: Tue Nov 18, 2025 1:49 am

Re: Cant get caustics from top view through water

Post by microvswind »

i change blender from 4.5 alpha to 4.5 lts,works.
thx so much for you guys help.
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