Low Key is the 14th studio album, and fifth cover album, by Filipina singer-actress Regine Velasquez-Alcasid, released on November 14, 2008 in physical format (cassette & CDs) and digital. The album was Velasquez`s first album with Universal Records. It was certified gold a week after its release with sales of over 12,500 units on its first day a.... Low key as a term used in describing paintings or photographs is related to but not the same as low-key lighting in cinema or photography. A painting or image is low key if its dominant values are dark. ...
A dark image that is intentionally lacking in highlight detail
Consistent use of dark values within a given area or surface.
A dark image that is intentionally lacking in highlight detail. 
[adj] - restrained in style or quality
Term describing a photograph in which the tones are mostly dark and there are few highlights. (see High key)
low-keyed adjective restrained in style or quality; `a little masterpiece of low-keyed eloquence`