Photo: ©2012 Jo Brady
One of the many questions I get in my Photoshop classes is how to do selective black and white photos where the subject is in color but the background is desaturated and turned to black and white. One of my Photoshop students, Jo Brady, happened on this fox in her yard one morning and caught it in this great picture. She wanted to turn the background black and white while leaving the fox in color to enhance its presence. So I thought I would share a step-by-step process on how to do this in Photoshop CS6. You can also do this in older versions of Photoshop including Elements.
The first thing we need to do is make a selection around the fox. When making a selection around a complex object like the fox I like to always try the Quick Selection tool first. The Quick Selection tool is easy and fast and if it doesn't work it only takes a second to try but when it does work it saves you lots of time.
To use the Quick Selection tool, think of it as a paint brush where you paint over the areas you want selected. Photoshop will analyze the area you paint over and expand the selection where it thinks you want it to. To make sure you don't paint over areas you do not want selected you might need to adjust the size of the Quick Selection brush in the Tool Options at the top. You don't want to make it too small because it will take longer to cover the area so make it just small enough to get between the small areas.
The Quick Selection tool has a mind of its own and will sometimes grab areas you don't want selected. If you need to adjust the selection, hold the Alt key while painting and the Quick Selection tool will subtract the selected areas. Be careful what you paint over, Photoshop watches everything you select with the tool and adjusts accordingly.
With the background now selected, go to the Adjustment Layer menu and choose a new Black and White adjustment layer. With this adjustment you can adjust the color sliders to get the desired look you want out of the black and white area. I'm using the Maximum Black preset to get the background darker and help separate the fox from the background. If you're using Photoshop Elements or an earlier version of Photoshop you can use the Hue/Saturation adjustment layer instead. I like to use the Black and White adjustment layer whenever I desaturate an image because of the control of color to grayscale options.
Now we have the basic conversion done with the fox in color and the background in black and white. Be sure to view your image at 100% to make sure the mask edge looks good. In this image, the fox has hair sticking out around his body so the edge doesn't look that good right now. Hair is always a problem with selections and can be difficult to work with in a mask. If the edge is too sharp you can try feathering the edge first to see if it fixes it. Be sure to select the mask icon in the Layers panel and in Photoshop CS6 you will go to the Properties panel and adjust the Feather slider. If you're in CS5 or CS4 you will use the Mask panel to adjust the Feather slider. And, if you're in an earlier version of Photoshop or Elements you will need to select the Mask icon and apply a Gaussian Blur filter to the mask in the menu Filter>Blur>Gaussian Blur.
For this image I'm not happy with the Feather results on the hair so I'm going to try a different technique. I'm going to use the Edge Detection feature introduced in CS5. With the mask icon selected in the Layers panel, go to the Properties panel in CS6 or the Mask panel in CS5 and click on the Mask Edge button. The Refine Mask dialog box will open and we will have many options to adjust the mask.
The first thing you want to do is adjust the View Mode at the top of the dialog box so you can see how the adjustments affect the mask. Click on the View button and choose On Layers option. This will let us see the effects on the image in real time. Now select the Smart Radius in the Edge Detection section to see if this automatically fixes the mask around the hair. The Smart Radius will try to figure out what should and should not be masked. Adjust the Radius amount to expand the Radius and encompass the hair if needed. Sometimes this works great on its own but other times it will not figure it out the edge on its own and you can try using the Refine Radius brush tool to adjust areas around the hair.
Select the Refine Radius brush tool to the left of the Edge Detection section and paint over the areas where the mask does not look good over the hair. If you go too far outside the hair or object you can choose the Erase Refinements Tool in the same place as the Refine Radius brush tool by clicking and holding on the icon. If you need to move around the photo and paint over areas not visible in the window hold the Space Bar on your keyboard which will temporarily turn on your Hand tool and move the picture to where you ned to. Once you're happy with the mask edge, hit the OK button. We should now have a really good mask around the object.
Now I want to ad a bit of contrast to the fox, and since we now have a good mask built we can use it to make other adjustments on the subject. To use the same mask, Command-click on the mask icon in the Layers panel (PC users: Control-click).
This loads the mask as a new selection but right now the background is selected. Now were going to Inverse the selection again in the menu Select>Inverse. With the subject now selected, choose a Levels adjustment from the Adjustment Layer menu and you can adjust the Black and White triangles to create contrast or adjust the middle Gray triangle to adjust brightness. The same process could be used to add any adjustment layer you want to the subject.