If you should want to change the color of a dress without affecting the rest of the image, you can do it with just two Adjustment Layers in Photoshop -- Black & White and Solid Color.
Step 1 : Click the Adjustment Layer button. Click on Black & White.
Step 2 : The Black & White Adjustment layer forms above the Background Layer, containing the image. The Layer Mask is selected. You can make this out from the tiny border around the Mask.
The image looks like this.
Step 3 : Press CTRL+I. The White Layer changes to Black.
The image again appears in color.
Step 4 : Click the Brush Tool or just click b on the keyboard.
Step 5 : Select a large, soft round Brush. The Foreground Color should be set to White. A shortcut to make the Brush bigger is to use the ] (right bracket) and to make it smaller [ (left bracket). To make the Brush hard press SHIFT+] (right bracket) and to make it soft SHIFT+[ (left bracket).
Step 6 : Zoom into the image to paint, or you might leave some portions behind, especially at the edges.
The color of the dress has been completely removed. If you should paint out a portion that you should not have, press x on the keyboard to change the Foreground to Black. Paint out the mistake. Press x on the keyboard, to switch the Foreground Color to White and continue painting till the color is removed.
Step 7 : Make the Gray lighter by increasing the Reds in Black & White.
Step 8 : Click the Adjustment Layer button. Click on Solid Color.
Step 9 : The Pick a Solid Color opens. It is the same as the Color Picker.
The column in the middle is called the Spectrum. Note there are tiny sliders in the bottom.
Step 10 : Drag the slider in the middle. The color will change as you drag. Click on a color. The 'new' at the top changes to the color clicked. The numerical value of the color appears at the bottom.
Step 11 : Click OK in the Color Picker. The Solid Color adjustment layer appears at the top.
Step 12 : Click the Mask to make it active. A tiny border appears around it as soon as you click.
Step 13 : Press CTRL+I to invert the Mask. The Mask changes from White to Black.
Step 14 : Change the Blend Mode to Color.
Step 15 : Click on the Black & White Layer Mask.
Step 16 : Press ALT. Drag up the Mask to the Mask of the Color Fill Layer.
Step 17 : This dialogue box appears. Click Yes.
The Color of the dress has changed, but nothing in the rest of the image has been affected.
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