Yeah. 

Again, make sure you have a background copy because
" It is your Raw comparison source, as well as where you'll copy off parts of the image in case you screw up during editing the Background"

wiki.yuriproject.net/editing_tutorial#background_copy

Blacks should be black (remove the specks)
To check,  you can slide the white bar to the left (~30)
http://puu.sh/lgqpM/cd8f825b93.jpg