Higher-Vision is the extension of vision beyond the physical level up into higher levels of reality. Astral clairvoyance is only the beginning of Higher-Vision which extends further into sight on the mental, causal, manasic, buddhic, atmic, and in a very subtle way to higher levels of reality. (For more information about these levels go to The 7 Universes and proceed through the Tour of Your Energy Bodies As Seen with Higher-Vision.)
Higher-Vision is awakened with specific intensive meditation practices along the line of concentration/samadhi/samatha.
Higher-Vision takes the blinders off to the seeing of the rest of reality; allowing energy conditions, causes, and solutions to be revealed.