OBSERVING
All things equal (Seldom) -  Aperture Rules  Seeing is Critical,  Dark Sky
shows more,  In Dark Sky w/ Fair : Eye, Optics, Transparency, & Seeing
(with exceptions):
       Eye - Mag 6,  Separation 500 Arc Seconds
       50mm Binos - Mag 9,  Separation 4 +/-  Arc Seconds
       90mm Scope - Mag 10,  Separation 3 Arc Seconds
       4" Scope - Mag 11,  Separation 2 Arc Seconds
       8" Scope - Mag 12,  Separation 1.5 Arc Second
Purkinje Effect - Human Eye less sensitive to color in low lite.  More
       sensitive to Blue & Green, makes Dim Star near Brite Star appear more
       Green or Blue than if seen isolated.
Dazzel Effect - Human Eye sees more White with increased briteness of Star.
        Increased Aperture increases Dazzeling.
Contrast Color Effect - Human Eye sees Color/Tint more intensely if Star seen
        near Star of Contrasting Color/Tint
Analogous Hughes Effect - Human Eye sees Color/Tint less distinctly if Star
        seen near Star of similar Color/Tint
DEFINITIONS
Averted Vision - Concentrating on object not in Center of Vision.  Periphery
      more Lite Sensitive in Dark. Cones more concentrated in Center of Vision
      Rods in Periphery
Components - Stars in Double or Multiple Star System
Dark Adaptation - Process by which Human Eye more sensitive to Lite.  Most
      Adaptation occurs 15-20 mins., then for 30-45 mins. Eye produces chemical
      to further increase Lite Sensitivity
Direct Vision - Concentrating on object in Center of Vision
Double Star - 2 Stars that appear close
      Naked Eye Double - 2 Stars that appear close to the Naked Eye
      (1) Optical Double - 2 Stars that appear close in a Telescope
      (2) Optical Double - 2 Stars that appear close in a Telescope, but are not
            Gravitationally Bound
Binary - 2 Stars that are Gravitationally Bound, in Mutual Orbit
      Non Visual Binary - 2 Stars Gravitationally Bound, but not Optically Visible
Multiple Star - 2+ Stars that appear close
      Naked Eye Multiple - 2+ Stars that appear close to Naked Eye
      (1) Optical Multiple - 2+ Stars that appear close in Scope
      (2) Optical Multiple - 2+ Stars that appear close in Scope, but not (all)
             Gravitationally Bound
Multiple Star System - 2+ Stars Gravitationally Bound, in Mutual Orbits
Position Angle - Direction of Secondary/Component from Primary, measured
      Clockwise from North as 0
Primary - usually the britest Star of Double or Multiple Star
Secondary - usually dimmer of Double Star
Seeing - how Steady Telescope Image is,  effected by : Tube Currents -
      Turbulence & Temp. Differences in Telescope
      Ground Seeing - Turbulence & Temp. Differences in Observing Area
      Atmospheric Seeing - Turbulence & Temp. Differences in Atmosphere
Transparency - Clearness of Sky