what is metamerism

vishal singh, 13 years ago

Grade:11

2 Answers

AKASH GOYAL AskiitiansExpert-IITD

420 Points

13 years ago

Dear Vishal

When two color samples appear to match under a particular light source, and then do not match under a different light source this is " metamerism."One can conclude that the spectral reflectance distributions of the 2 samples differ slightly, and their plotted reflectance curves cross in at least 2 regions. By illuminating them with lights with consideralby differing spectral power distributions you can witness and even exaggerate the visual differences between the 2 samples. The example below is how most remember this is the most commonly experienced form of metamerism.

Example: most people have experienced sample metamerism when putting on two socks that appeared to be black while in the bedroom (which may have incandescent lights), but later finding that one is black and the other is blue upon stepping into the kitchen (which may have fluorescent lights). The differences in the wavelength distribution between the incandescent and fluorescent lights interact with the differences in the spectral reflectance curves of the socks to make them appear the same in one light source and different in another.

Explanation: Incandescent light bulbs contain relatively little light in shorter (blue) wavelengths, and thus it would be more difficult to distinguish blue colors in such lighting conditions. The fluorescent illumination in the kitchen emits more short-wavelength light, and thus the dark blue can be more easily distinguished from black. In incandescent light, the socks are a "metameric match"; in fluorescent light, they do not match.

All the best.

AKASH GOYAL

AskiitiansExpert-IIT Delhi

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Approved

sanan kashyap

32 Points

13 years ago

This type of isomerism is due to the difference in the nature of alkyl groups attached to the polyvalent atoms or functional group. Metamers always belong to the same homologous series. Compounds like ethers, thio-ethers ketones, secondary amines, etc. show metamerism.

Metamerism

• If same polyvalent functional group is there in two or more organic compounds, then chain or position isomerism is not possible, there will be metamerism e.g.,

Metamerism