Radially distorted bokeh with the physical lens shader?

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I'm trying to replicate the look of radially distorted bokeh that comes from specific lenses.
I've attached an image example of the look I'm going for.

I would love to achieve it in render (with the physical lens shader?).

I noticed on the physical lens shader there's an option for bokeh rotation.
I would be able to fake this distorted effect if I were able to use a texture to control bokeh rotation or use the screen space position to control bokeh rotation.

Any advice or pointers are appreciated.

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Screenshot 2024-01-22 175332.png (1.2 MB)

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Hey! Sorry if this is way too late but I also wanted to create this effect and figured it out! This effect is known as "cateye" bokeh or Optical Vignetting. Unfortunately, there's no good way to achieve this using the Physical Lens VOP node.

What you can do instead is implement what is shown at this link [www.creativeshrimp.com]. It's for Blender, but the setup in Houdini is essentially the same. I created a plane with a hole cut out and then used a single xform prim to move both the plane and camera with the same values. You can then play with the plane's scale and z-position to make the cateye effect more apparent.

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anamorphic.jpg (471.3 KB)

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It is somewhat possible with the lens shader (cpu only), I'm not completely sure it actually does any of the Optical Vignetting though.
Here is what I got when I played with something similar, rotating the bokeh and playing with the anisotropy




Attaching the hda if you want to take a peak beneath the hood, assign the vop as the lens shader(karma CPU only)
Edited by AslakKS - 2024年6月24日 16:42:19

Attachments:
vop_Aslak.aks_lens.1.0.hdalc (22.4 KB)
hindie_SyNQDS1HZG.png (1.5 MB)

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