Why does the spectrophotometer gives negative absorbance values?

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zzz

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V. N. Ravi Kishore V.

Negative absorbance arises whenever intensity transmitted from the sample is higher than intensity transmitted from the reference. It is generally an experimental artifact.

What is the reference you are using?

Paula Nuñez

supposedly LB broth

Is your result reproducible?

Sharifah Farhana Syed-Ab-Rahman

Most probably the settings of the spectrophotometer