Certain instrumental errors could be averaged out by reversing the telescope on its mounting.

With the current methods, the instrumental error in the measured hairpin length is 1-1.5 nm.

Gravimetry provides very little room for instrumental error and does not require a series of standards for calculation of an unknown.

Many of us, of course, continue to support more modest funding of gravity research using small prototypes, in which major problems of noise and instrumental error are still causing problems."

Even after fitting a planet and a trend, it was noted that the residual velocities were still around 3.4 m/s, significantly larger than the instrumental errors of around 1.7 m/s.

At first he thought this must be due to some instrumental error, but after closer examination and repeated study of the effect as manifested by many different stars, he came to the conclusion that its origin must be sought in some quite different source.

Theodolite (Describing a theodolite as a transit may refer to the ability to turn the telescope a full rotation on the horizontal axis, which provides a convenient way to reverse the direction of view, or to sight the same object with the yoke in opposite directions, which causes some instrumental errors to cancel.)