Unreal Engine
Virtual Lens Experiments
I'm a total lens nerd, and so when I found out last year that with modern path tracers you can essentially simulate the characteristics of vintage lenses with real physics, I embarked on a few late nights of experimentation.
The Inspiration
William Landgren's Pro Lens 2 for Blender
Joshua Kerr's Virtual Glass for Unreal
NEW: Håvard Dalen's Lens Sim for Blender
My Own Process
With the help of a website called Photons to Photos, I was able to source the diagrams and true measurements of a 1950's Leica "Xenon" 50mm f1.5.
Houdini to Unreal
I built a little HDA that lets me take the above data and procedurally build and adjust the actual lens elements in terms of geometry. I then bring that into Unreal, and with a proper path traced glass shader, then comes the real experimenting!
Results
Left is through the virtual lens, right is a "clean CineCamera". The result is super interesting: you get accurate lens distortion and qualities seen through a lens built in that era. The close focus is horrible, and when shot wide open (with an actual aperture geometry open all the way), the bokeh, fringing, and overall halation look super organic. Also, there's no such thing as simulating anti-glare coating, so the blacks are lifted since there is sunlight directly hitting the front element of the lens. Nerdy!
5/24/24