Purple grenadier Purple grenadier The purple grenadier ("Uraeginthus ianthinogaster") is a common species of estrildid finch found in eastern Africa. The length averages 13.3 cm (5.25 in). All ages and sexes have a black tail, and adults have a red bill. The male has a cinnamon-colored head and neck with a blue patch surrounding the eye. The rump is purplish blue and the underparts are violet-blue with variable rufous patches. The female is smaller and mostly cinnamon brown with white barring on the underparts and silver-blue eyepatches. Juveniles are like females, but mostly unbarred tawny-brown with a reddish-brown bill. The song (in
Purple fringing usually attributed to chromatic aberration as described above, although it is not clear that all purple fringing can be explained this way. Other attributed causes of purple fringing in digital photography include many hypothesized sensor effects: Commonly advocated methods of avoiding purple fringing include: Post-processing to remove purple fringing (or chromatic aberration in general) usually involves scaling the fringed colour channel, or subtracting some of a scaled version of the blue channel, or other blue-channel tricks. Purple fringing In photography (particularly digital photography), purple fringing (sometimes called PF) is the term for an unfocused purple or magenta "ghost" image on