In this video a field-scope is tested on the binocular chair, in preparation for a nighttime tour. The observing area will be the entire region surrounding the zenith. This area of the sky is generally the darkest and clearest, where there is less effective atmospheric thickness, and less skyglow. The extra magnification of the field-scope can be helpful for picking out smaller DSOs and galaxies.
Beforehand, a couple of easy one-time coarse adjustments were made to accommodate the field-scope on the bino-chair. Later at night, no coarse adjusting will be needed while doing the actual observing.
After settling into the bino-chair, the field-scope is brought into the best eye position, using the teeter and cradle. This eye positioning is maintained very well later when the chair is tilted fully back. The viewing elevation can be finely tuned with the teeter/cradle. For panning, the other hand lightly pushes the drive wheel. If both hands are released from the controls, the viewing direction remains steady.
At any time, the field-scope can be shifted up out of the way, to look at the sky naked-eye or to use a planetarium app. The field-scope can then naturally be returned down to find the same part of the sky.
When zooming in with the field-scope, the sidereal motion of the stars becomes more apparent….. a little pressure on the azimuth and altitude controls keeps any target centered.
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