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
No finder is provided with webcams or astronomical CCD cameras for position object on chip; only by taking test exposures may achieve both sharp focus and correct object position; flip mirror help to be centred and focused remotely on chip via eyepiece
Astromania 1.30inch Mars Filter is an excellent multi-purpose filter for viewing all features of Mars; polar caps stand out prominently; landscape features like mare and highland mountain ranges are easily separated and resolved; polar hazes and cloud cover become visible
Fully-coated Mars filter: An invaluable tool for any planetary viewer with an interest in the red planet; increases contrast to bring out subtle details on the disc of the red planet