Procedure
Whether I sweep with alarmist (binoculars and the 47cm reflector) or equatorial (25 cm reflector) mount, my sweeps are in only one direction. This prevents "under lap" (missing portions of the sky) at either end of the sweep. With a clock drive, or covering polar or (due) southern regions, bi-directional horizontal sweeps may be acceptable. With an altazimuth mount, I sweep in a horizontal direction, sweeping in one direction, then swinging back to the original azimuth before raising (western sky) or lowering (eastern sky) the instrument. With the binoculars, the sweep length may be as long as 90 degrees, but averages 45-60 degrees. With the 47cm reflector, my sweeps are much shorter, typically about 20 degrees.
With the equatorial mount, I sweep along the same RA, the declination changes by between 30 and 40 degrees. The shift in RA is made at the end of the sweep closest to the equator, otherwise sections will be missed as one sweeps toward the equator.
A sweep takes 2-4 minutes. I keep the instrument in constant motion. Going too fast causes things to be missed, slowing down takes up too much time. With the 47 cm reflector, searching high in the sky, I pick up most nebulous objects on the Atlas Of The Heavens (galaxies to mag. 13) and often go beyond. With the binoculars, where my average sweep elevation is 25 degrees, I normally pick up everything brighter than mag. 10.5, and often go deeper.
I keep extensive notes of where I've swept, how long it takes and what I have seen. The list becomes long when I sweep the Virgo and Coma Berenices regions, which I do as much as any other area.
