An adjustable stand having a first spindle, a second spindle and a flange for connection to and positioning of an optical observation instrument. Positioning of the instrument relative to the stand is maintained by a torque compensation device respectively arranged with at least one of the spindles to compensate against torque caused by the mass and positioning of the instrument and spindles. Each torque compensation device includes a brake for securing the spindle, a spring, a motor for adjusting the spring tension, and a motor controller which includes a transmission device with a transmission ratio deviating from 1:1 and which is positioned between the spring and the spindle. The motor controller controls the spring tension by selectively rotating the motor based on instructions from a control unit, which receives signals from a spindle-position sensor and a spring-tension sensor and automatically provides counter-torque rotational movement instructions to the motor controller.
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