Maya Camera Attributes
The following image shows in green which Maya camera attributes are taken into account by Maxwell:
The near and far clipping distances are applied when "Auto Render Clip Plane" is off, just like in the Maya Software renderer; this feature is called Z-clip planes in the main Maxwell documentation. The horizontal and vertical film offsets are used to simulate a Shift Lens. Maxwell can only render perspective cameras, orthographic views are not currently supported.
Maxwell-Specific Camera Attributes
The plug-in adds a group called "Maxwell Render" at the bottom of the camera Attribute Editor. This contains the Maxwell-specific attributes:
Since the Maxwell camera is very similar to a real-life DSLR camera, the parameters in this group should be intuitive to anyone familiar with traditional photography: shutter speed, f/stop, ISO, exposure mode, diaphragm. The Camera section in the main Maxwell documentation contains a detailed explanation of how these features work.
Note: If this group does not appear in your scenes, make sure "Auto Load" is checked for the Maxwell plug-in in the Plug-in Manager.
Focus
Unlike other render engines, Maxwell always computes depth of field. This effect is influenced by 4 factors: the size of the objects, the focal length, the f/stop and the focus point. It is important to use realistic camera settings and model sizes in order to obtain correct renders.
The focus plane is always parallel to the camera film plane. By default, it is placed at the center of interest of the camera - the point around which the camera orbits when you manipulate it in the viewport. This point coincides to the aim locator when the camera controls are set to "Camera and Aim" or "Camera, Aim and Up". The f/stop number controls the depth of the focus volume, or how much it extends in front and behind the focus plane.
If you need to control the focus point independently of the aim point, you can check the "Manual Focus Distance" box in the Maxwell attributes group and adjust the "Focus Distance" attribute. The focus plane will still be perpendicular to the camera aim vector, but it will be placed at the specified distance from the camera position.
