Hi.

Thank you for your comment about Reality.

Hiding lights in Reality is done in the same way that you do it in real life...

You might wonder what that is. The answer is... you move the lights out of the frame :). The idea of invisible lights is a bad habit perpetuated by some 3D software and has no reason to be with a physics-based renderer. 

In fact, if you have visible lights in the scene and they should not be there that is a sign that your lighting scheme needs to be changed. 

Every photograher deals with the same issue and I can assure you that they don't erase the lights in Photoshop. 

If you have specific examples I can help you with the modifications but lighting in Reality and LuxRender is done in the same way that is done in real life, which makes it predictable and realistic.

Hope this helps.

Paolo

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