Converting a selection to Black & White

[bartonlew]

SCENARIO 1:  Somehow in the application of adjustment layers, the text inside the red rectangle below turned from black to green.  So I lassoed the area and clicked on the letters with the Color Range tool, then applied a Black & White adjustment layer and brought all the sliders down as low as they could go.  This resulted in text that was a very dark green, not true black (screen shot 2).  Obviously I don't understand how this adjutsment layer works. 

SCENARIO 2:  To the left of that area is more text which I turned black by selecting it and applying a Color Fill Layer and choosing #000000.  That worked, but the black was too dark for my taste.  So I applied a Curves layer to lighten the shadows somewhat but this resulted in exposing green (see screen shot 3).  How can I lighten the shadows here (text letters in the area to the left of the red rectangle) without exposing the original green again?  Thanks.  

[Bojan Živković · Accepted solution]

Try placing the Black & White adjustments layer at the top of the layer stack.

[bartonlew]

Yep, that worked.  Thank you!

[Trevor.Dennis]

I can't say for sure that this will work without seeing your layer stack, but when Curves and Levels adjustment layers adversly affect colour, you can fix it by setting the Adjustment Layer's blend mode to Luminosity.