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Hidden from Camera
This option allow allows you to hide make an object not to appear invisible in the final image, but its presence affects all the objects around it (shadows, reflections, global illumination).
This object (left) disappears when it is hidden from camera (right), but its presence continues
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to affect the whole scene
An interesting use of this option is to hide emitters to appear in the rendermake invisible emitters, but maintaining the light they cast in the scene.
Hidden emitter
The emitter at the top of the box is hidden to the camera
Hidden from Reflections/Refractions
This option hides your object to be seen in the reflective and transparent prevents the object from appearing in the reflections of other objects, or from being seen through transparent, refractive objects.
This object (left) is visible in the reflective object and through the transparent
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object. Right image shows how the object is invisible in the cylinders reflection and also when seen through the glass plane.
Hidden from Global Illumination
This option allows you to skip With this option from the Global Illumination calculations. This way, you can avoid an object to cast shadows and affect other objects with its color bleeding. turned on, the object will not affect the global illumination in the scene - it will not cast a shadow or affect color bleeding in the scene.
Enabling this option (right) you can force an object not to cast shadows nor affect other objects with its color bleeding
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Hidden to Z-clip Planes
Z-clips clip Planes define near and far distance boundaries outside of which the objects will not be considered by the render calculations. Please see the Z-clip planes page for more details.This option is useful when you want to clip your scene with a near and far plane to avoid unnecessary calculations, except for certain particular objects that you do not want to be affected by the Z-Clip planes.