For Precise Focusing: Flip mirror makes easy to find exact focus point and also correct position for astrophotography; small black box has a moveable flip mirror which shunts light path 90 degree upwards; alternatively lets it pass through unhindered
Always Sharp: If tilt mirror to 45 degree position; object will appear in eyepiece and precisely focus it as usual; helical focuser on flip mirror lets to make eyepiece and camera exactly parfocal; this means elements will be in focus at the same time
An object that is accurately centred in the eyepiece will be simultaneously centred in the camera's field of view; you no longer have to worry about whether the object is correctly positioned on the chip - you know it will be
Wider 58 Degree Field of View: Comfortable eye relief averaging 16 mm across the series and focal lengths is between 2.5 mm to 25 mm; giving maximum detail and definition across the entire 58 degree field of view
Multi-coated Lense Design: Each eyepiece has 5 lens elements in 3 groups; with retaining high transmittance and contrast ratio with least lateral cchromatic aberration and scattering phenomenon; having a wide view