Different SimuLens and Physical Sky settings 

Maxwell Render SimuLens™ system allows the user to define a pattern to simulate the shape of the camera diaphragm that will model the pattern of light reaching the film, creating realistic lens diffraction effects (also known as glare). Diffraction happens when light goes through small holes, causing interference patterns. It is a very important phenomenon in optics, as it explains why for example a perfect telescope cannot be built. Light will always cause slight interference patterns because of the optical components used, causing the visual “artefact” known as diffraction/glare.

Furthermore, with the Simulens™ system, users can add a second pattern which defines 'obstacles' in the lens such as dust, water drops, fingerprints or eyelashes adding to a more realistic diffraction effect.

A second control was added to the lens diffraction feature, called Frequency, which lets you adjust the amount of colouring effect of the diffraction.

Another new parameter part of SimuLens™ is Lens Scattering, which simulates the scattering of light inside a lens system. This effect is typically called bloom.

These advanced controls bring a new level of quality and realism to computer graphics. Users can now have control over Diffraction, the frequency of Diffraction, and Lens Scattering to simulate bloom effects.

All these features are combined under the new SimuLens™ system which is also compatible with Multilight™. 



  • For Simulens to work, setting an Aperture Map is mandatory as it describes the shape of the diaphragm. 

  • The Obstacle Map is optional but adds more variation to the effects.

  • After setting the Aperture Map, you have to activate the Diffraction option. This is also mandatory if you want to see the interference patterns (glare). Deactivating it, disables the glare (but not the Scattering or Devignetting effects).

  • Play with Diffraction and Frequency levels to get the desired effect. 

  • The Scattering effect is independent of all the above and creates a more general bloom in the image.

  • The Devignetting effect is also independent of all the features described before. It allows to reduce or increase the natural darkening of the images at the corners that occur when the angle of the lens gets wider.

Here is a general tutorial about Simulens.

The SimuLens adjusment panel