Simple past tense and past participle of underexpose.(verb)
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Use "underexposed" in a sentence
"The MP990 printers utilizes the Auto Photo Fix II feature to help users get the most out of photos and help to correct many common photo errors, such as underexposed images."
"The solution to adding detail to the sky is the take a picture that is underexposed, meaning that I make the shadows darker then they really are."
"Fine print head technology, and an improved Auto Photo Fix II feature that resolves common photo-printing errors, such as underexposed images, through Multi-Zone Exposure Correction and improvements in overall face detection, scene analysis, plus brightness and saturation correction."