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Asticles
07-01-2017, 04:37 PM
Hi guys,

I'm trying to find any tuto of this but nothing.
How was the technique to tonemap in vpr using a plane in front of camera?

Thanks!

Iaian7
07-01-2017, 08:20 PM
I'm not sure what tutorial you're referring to, but the concept piqued my curiosity enough I built a test scene of my own! You can use the Refraction node without any IOR to "access" the scene image, then modify it using any nodes available in the surface editor (I would typically use DPont's Curves node, but in this case I built it using only LW native options). The output can be piped to the diffuse, and that's pretty much it.

Without the filtering geometry in front of the camera:
137255

With the filtering geometry in front of the camera:
137254

The nodes look like this:
137253

The results feature a simple form of highlight compression and shadow/highlight colouration (again, DPont's Curves node would be vastly superior, but this is a quick test :D ). The attached .zip file contains the sample object and scene pictured above.

gar26lw
07-01-2017, 08:43 PM
I have a feeling this was mentioned by gerardstrada either here or in hdri mag. Could be wrong.

Asticles
07-02-2017, 04:32 AM
Thanks for your help !!!!

Asticles
07-02-2017, 05:08 AM
Hi,

Looking at your scene, just tried with this and worked.

Thanks!

I expect LWnext will have exposure controls within camera so you can preview it within vpr.

gerardstrada
07-05-2017, 06:20 AM
I have a feeling this was mentioned by gerardstrada either here or in hdri mag. Could be wrong.
Yep, in both, HDRI3D magazine (2007 article) and here (http://forums.newtek.com/showthread.php?136662-LightWave-and-Wide-Gamut-monitors&p=1337325&viewfull=1#post1337325). The trick has been around for many years. We used to use it for gamma correction with FPrime but it can be used for proper colorspace correction, tonemapping, color rendering, colorgrading, custom LUTs and many many other things. Hope post filters could be recognized directly in VPR in future LightWave versions.



Gerardo