Lens Distortion grids…

Flame Tips and Tricks
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Missed Siggraph last week, but always appreciated the feeling of community and sharing it brought.

In that spirit…

I’ve been thinking about datasets, coming to the conclusion that the strength of a library is not its contents, instead it’s in the curation/usage of the data.

Recently I’ve been diving back into RnD of cinema lenses for consistent workflows with houdini, unreal and flame.

Lens distortion is one of many factors that give different lenses a particular personality.

Over the last couple of decades I’ve accumulated a wide range of lens grids so I decided to make a coherent set of stMaps that are easy to plug in.

Each set includes distort/undistort map in 32bit EXR. These maps will work in any app that supports the workflow.

Cinema lenses are largely handmade so DO NOT assume these will replace shooting production grids for your tracking team.

Even lenses of same type/manufacturer can vary.

If you want your 3d tracks to stick, trust the stMaps that come back from your tracking team.

These ARE helpful to create looks for MoGFX or to add to CG renders to make them feel more cinematic.

This set of 133 spherical and 83 anamorphic lens maps should work for such creative pursuits.

True lens models include breathing, flares/glares, vignettes and bokeh as well as mappings for focus, iris and zoom pulls.

Cheers-

Andy Davis

www.imag4media.com

Here are the grids:

UPDATED LINK:

(broke my dropbox limits)

Links worth checking out for more RnD about lenses:

https://vimeo.com/search?q=five%20pillars%20of%20anamorphic

https://www.sharegrid.com/learn/lens-sets

https://www.cinelensmanual.com/

10 Likes
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thank you for this!

zeiss actually made a app to generate STmaps and shading and all that also, i never gotten a lens/camera combination that would work for it however.

I asked them and they said there is such minimal change between models of the same zeiss lens, I find this weird as I have always heard that each lens is unique , but maybe in zeiss world that isnt the case? idk, probably some handmade cookes from 1956 are not what they have in mind.

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The ZEISS app works well actually, even tho it’s a paid app.
Worth checking out. I’ve used it on a few jobs.

These maps could work in a pinch for comp work too.
But this involves being aware of the filmback matching as well.
(No news for you Finn, but perhaps to other folks)

-A

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I’ll also post a version here using the matchbox outputs from 3de to flame. They take up a lot less space than the EXRs, but wanted to share something that was app agnostic.

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very dope, I have tried to use the zeiss tool even talked to them directly and my camera/lens combo wasnt certified to even work, was a alexaLF with some kind of zeiss lens… anyhow the idea is great and much more data than the ACs I work with can usually pull off… :smiley:

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These are really only the initial building blocks for true lens models.

Here’s a screen grab of my WIP database:

lensDB
lensDB1920×1080 181 KB

and a link showing WIP access of CSV data thru Houdini:

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very cool stuff!!