Why black hair and black background same color (no difference ) after the printing in canon

Black hair in a photograph isn't going to be all black. There will be variations of color and grayscale, even in a back-lit silhouette. Is the image something that is contained in a clipping mask and set against a vector-based black background?

Is the black background color a plain 100% K black? Or is it a rich black using all four CMYK inks? If the image is RGB based and linked in the document rather than embedded (and converted to CMYK) the blacks in the photo image may print deeper or just different from the black background.

How is the "Handling of Black" set up in the preferences?

Exactly how are the blacks sets up in the file? Vector or raster elements?