An instrument can display a precise-looking number while its relationship to the quantity being measured is imperfect. Calibration examines that relationship using reference values under stated conditions.
Calibration and adjustment are related but distinct ideas. Learning how a reading compares with a reference does not automatically mean the instrument has been changed. The result can instead describe corrections or uncertainty that need to accompany its use.
Read the instructions for an instrument you already use. Notice its stated range, conditions, and any recommended checks. The purpose is to understand what confidence the reading supports, rather than treating the number of digits on the display as proof of accuracy.
- Identify the reference used for a check.
- Separate calibration from adjustment.
- Read the stated conditions and measurement range.
An example to consider.
A scale used for a small project can be checked with an appropriate reference. The check is more informative when its conditions are recorded.
Put it in perspective.
Change one part of the setup and notice what follows. A small, described comparison can make an abstract mechanism easier to reason about.
Follow a related question
Record the support behind the pilot.
From a pilot to an ordinary dayCheck the actual interactive area.
Touch targets with room to moveKeep learning
Related background to continue exploring this subject.
NIST: the International System of Units NIST: statistical engineering
