MadSci Network: Engineering |
There are a variety of techniques available, depending on exactly what you mean by "measuring color." The simplest is to use the APHA scale, which uses a set of 12 tubes that gradually get darker -- you fill a sample tube with the test water, and determine the number by comparison. This will give a result that is one-dimesional, and doesn't really care what particular shade it is, only the depth of shade. If you wish to determine a color value more specifically (i.e., whether it's green or blue or orange as well as depth of shade), there are two basic ways, both of which involve passing light through the sample and measuring it. The simplest would be using an adapter that allows a tube of a specific size to be placed in the light path; some electrospectrophotometers have that kind of adapter. Another way is to use a sample cell with a cap; the cap reflects the light back through the sample for measurement. In either case, you would have to establish some kind of scale to determine what parameters are important to you.
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