Enable Exposure – Enables V-Ray exposure control. When enabled, the F-number, Shutter Speed ^-1, and Film Speed (ISO) settings will affect the image brightness. If enabled, Unreal's tonemapper and PostProcess effects will be disabled when looking through the camera and Enable Viewport Rendering is On .
3ds Max Compatible – Enables 3ds Max compatible exposure control. Enable Exposure must also be checked for 3ds Max exposure to work.
Film Speed (ISO) – Determines the film sensitivity. Smaller values make the image darker, while larger values make it brighter.
Shutter Speed S^-1 – Specifies the shutter speed, in inverse seconds, for the still photographic camera. For example, shutter speed of 1/30 s corresponds to a value of 30 for this parameter.
F-number – Determines the width of the camera aperture and, indirectly, exposure. If the Enable Exposure option is checked, changing the F-number will affect the image brightness. If Focus Method is set to Manual or Tracking, F-number will control the strength of the DoF. Low values will produce a strong DoF effect and high values will produce little DoF.
When adjusting F-number for desired DoF effect you need to compensate the exposure with either ISO or Shutter Speed S^-1 values.
White Balance – Allows additional modification of the image output. Objects in the scene that have the specified color will appear white in the image. Note that only the color hue is taken into consideration; the brightness of the color is ignored.
Reinhard Burn Value - Specifies the multiplier applied to bright colors.
Distortion Type – Specifies how the distortion is determined.
Quadratic – Distortion is increased as the square of distance from the center. The default distortion type. It uses a simplified formula that is easier to calculate than the Cubic method.
Cubic – Distortion is increased as the cube of distance from the center.
Amount – Specifies the distortion coefficient for the camera lens when the Distortion type is set to either Quadratic or Cubic. A value of 0.0 means no distortion; positive values produce "barrel" distortion, while negative values produce "pillow" distortion.
NEW - Near Clip Plane – Specifies the offset from the camera (in cm) of the clipping plane. Geometry before this range will be clipped and will not be rendered.
Effect of Near Clip Plane will not visible in the viewport in UE 4.21.2.