How to convert a colored image to black and white using Gradient Map in Photoshop CS6-(Non-Destructive method)

There are  various ways of converting an image from colored to Black and White.Here we shall discuss the method that is non destructive which means that the method does not make any changes to the image.Photoshop uses a separate Gradient Map layer to apply the adjustments.

                                      

                 

                                                 Before                                After
1) Opening the image in the Photoshop window

Open the colored image in Photoshop CS6 by using the menu File > Open or by using the keyboard shortcut Ctrl + O.This will open a dialog box.Select the image by clicking on its name and click on Open button.

2)Setting the foreground and background colors
Before applying the Gradient map we need to make sure that the foreground /background colors are set to the defaults means black and white.For doing this we can press the keyboard shortcut D.
                                                    

3)Selecting the Gradient Map... option

After we see the image in Photoshop window we need to open the Gradient Map  properties window.For this we need to select the  Gradient Map option.There are two ways of selecting the  Gradient Map option.

a) Select menu Layer > New Adjustment Layer >  Gradient Map... 

We can see a dialog box asking the name of the new adjustment layer.By default Photoshop names it  Gradient Map 1.If we want we can type in any other name or we can leave it as Gradient Map1.Click on OK button after naming the layer.

                                         

b) The other way to get the  Gradient Map option is by clicking on the Create new fill or adjustment layer icon (half colored circle) in the bottom of the layers panel and selecting  Gradient Map... option.
                                                            

4) Gradient Map Properties panel

Now we can see a  Gradient Map Properties panel with a drop down for selecting gradient.By default the black and white gradient is selected.We can observe that the color of the image has become black and white.
                                                           
To hide the Gradient Map Properties panel click on the double pointing arrow on the top right of the properties panel.To exit out of the Gradient Map Properties panel click on the cross mark on the top right corner of the properties panel or click on the down pointing arrow at the top right corner of the properties panel and select close.

                                                 
We can see a new layer with a thumbnail added just above the image layer in the layers panel on the right side of the photoshop window.
                                                    

5)Saving the image

After we are satisfied with the adjustments we will save the image by selecting the menu File > Save or by using the keyboard shortcut Ctrl + S.This will open a dialog box where we can write the name of the image.After typing a name click on Save button.

The disadvantage of using this method is that we have no control over the adjustment.