Creating magazine advertisement style effect - color in grayscale image
A very effective image effect in print ads is showing one color while rest of the image is black & white. We'll try to achieve this effect in the image below. We'll make the whole image Black & White leaving only dark red portions like model's lips and dress.
Create a duplicate of the image layer.
From select menu click color range. Pick the ink dropper and click on model's dress. The preview area will show the red pixels selection.
Press ok and it will select the color range that you picked.
Still some portion of the dress is not selected. To increase the selection area, from select menu click similar.
It selects more pixels of similar color range but has also selected a portion of her arm and chin which is not required.
Zoom in on arm area.
Select magic wand tool. Press Alt key and click on arm selection. It will deselect the portion of the arm.
Similarly deselect the lower chin area that was included in the selection.
Now our selection is perfect. It includes only dress and lips of the model. Press Shift+Ctrl+i to invert selection. From Image menu select Adjustments>>Desaturate.
This will desaturate all area of the image except her dress and lips.