Low contrast images are created from a range of greys – there shouldn’t be any black or white in there. The problem with this is that you can end up with a tonally flat image that is just a dirge of grey.
The way of avoiding this lies with the Levels palette, specifically the Output Levels slider. To eliminate the black and white areas, move the black and white arrows towards the centre. Your shadows and highlights will now be made up of greys instead of B&W.
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