Publishers of technology books, eBooks, and videos for creative people

Home > Articles > Adobe Photoshop > Technique

  • Print
  • + Share This
This chapter is from the book

This chapter is from the book

Improving Selected Color Areas

Step 10: Type a W to switch to the Magic Wand tool and look in the Options bar at the top of your screen to make sure that the Tolerance is set to 32 and that Anti-aliased and Contiguous are on; these are the defaults. You are going to select parts of this image and improve their color balance and/or density. Start out selecting the green strip of grass that separates the field from the sky; you will have to Shift-click on it several times to get the entire green field. The center part of this area seems a bit too magenta to me. Click the grass and then Shift-click to add to the selection until you have selected all the grass. If you accidentally select something that you shouldn't, choose Edit/Undo (Command-Z) and try again. You can also use the Lasso tool (L) with the Shift key to add to the selection, or with the Option key to subtract from the selection. After you select the entire area, choose Select/Feather and enter 1 to create a 1-pixel feather. This feather will blend the color changes you will make along the edge of the selection.

Step 11: Choose Layer/New Adjustment Layer/Curves and name this new adjustment layer Green Field, and then press OK in the New Layer dialog. Use the pop-up at the top of the dialog to go to the Green channel, and then press the Load button in the Curves dialog to load the LockdownGreen curve from the Lockdown Curves folder within the Ch03.Preferences folder on the Photoshop CS Artistry CD. This places points all along the curve so you can make changes to a selected part of the curve. You could have placed these points manually, but the Lockdown Curves save you time. Click on the image with the Eyedropper and hold the mouse button down in the area where the green grass seems a bit too magenta. Look at the circle that appears on the curve. Move the cursor around a bit in the green area, while holding down the mouse, until you can see where an average magenta/green area is. At that point, Command-click on the image and Photoshop will place a point on the curve representing the place you clicked. Move that point in the curve diagram up and to the left to add green to that part of the curve. If you click in the grow box at the bottom right of the Curves dialog, you will get a bigger dialog that makes it easier to place more detailed points. When you are happy with your color changes, choose OK.

Figure 20.16Figure 20.16 Step 11: Create the selection of the green field with the Magic Wand and Lasso tools. If you find the tolerance value of 32 on the Wand too high, undo the selection and then press Return, 16, Return to change that tolerance without having to move the mouse. Remake your selection with this lower tolerance, which usually works better.




Figure 20.17Figure 20.17 Step 11: My final adjusted Green curve.




Figure 20.18Figure 20.18 Step 11: Measuring where the greens occur in the green grass. Command-Shift-click to add a point to the Red, Green, and Blue curves at the same time or just Command-click to add a point at the corresponding location in the curve you are currently looking at, as we did with the Green curve.




Figure 20.19Figure 20.19 Step 11: If you Option-click on the Green Field layer mask thumbnail, the rightmost thumbnail, you will see the mask created from your Wand selection. That is the only thing adjusted by this adjustment layer. Option-clicking a second time will return you to the display of the composite image.




Step 12: Use Command-Spacebar-click to zoom in on the trees; then select the darker parts of the big tree with the Magic Wand (W), as shown in the illustration to the right. Now go to Select/Grow and notice how this increases the size of that selection with that local area. Use Command-Z to undo the grow; then do Select/Similar and notice how this selects similar areas throughout the entire image, but with the Wand Tolerance at 32, this selects too much. Use Command-Z again, then press Return, then 12, then Return again and notice that the Wand's Tolerance is now set to 12. Now try Select/Similar again and you should see a selection that is like the one at the top of this page. You want to have the trees and bushes selected, but not the shadow areas in the foreground. Type an L to switch to the Lasso tool and use Option-Spacebar-click to zoom out so there is gray area surrounding the image. While holding the Option key down, circle the area shown in red in the illustration below and the Lasso tool will remove those foreground shadows from the selection. Now choose Command-F3 to create a new Curves adjustment layer and use the Curves dialog to brighten up the shadow areas and also the green color of the trees and bushes. Don't over do it here, you want small subtle adjustments like those shown to the right; otherwise, your trees will look posterized. When you are finished, you should have a Layers palette that looks like the one you see here. Now choose File/Save (Command-S) to save your work on this example so far.

Figure 20.20Figure 20.20 Step 12: Here we see the tree selected as we did using the Magic Wand tool. Now we choose Select/ Similar after setting the Magic Wand's Tolerance setting to 12.




Figure 20.21Figure 20.21 Step 12: After using Select/Similar to select the other dark green parts of the image, you then use the Lasso tool with the Option key held down to circle the area seen in red above here. When you release the mouse button, this part of the selection will go away and only the trees and bushes will remain.




Figure 20.22Figure 20.22 Step 12: My RGB curve for step 12.




Figure 20.23Figure 20.23 Step 12: My Green curve for step 12.




Figure 20.24Figure 20.24 Step 12: How your Layers palette should look after step 12. Notice that I have locked the top two layers so they can't accidentally be moved using the Move tool. To do this, just click on the Lock position icon for the active layer at the top of the Layers palette.




Step 13: Now we'll show you a useful tip you can use when selecting areas of isolated color. Type an L to switch to the Lasso tool and press the Return key to select the Lasso's feather value. Type in a 2, then press Return again to accept the feather change. Using the Lasso tool, make a very loose selection around the red barn, like you see in the illustration on the next page. Use Command-F4 to get a new adjustment layer of type Hue/Saturation and call it Paint the Barn. Now move the Edit menu to Reds and then move the Hue slider to –10, which will make things that are already red look like they just got a new coat of paint. Because there is no red component to the sky or green grass, this works well and saves you from making a detailed selection of the barn. Setting the Lasso feather to 2 before you started makes the edge of this selection soft, which helps it blend with the parts of the image that have not been changed. Choose Command-S to save your file.

Figure 20.25Figure 20.25 Step 13: Close-up of the Barn selection. Don't let the selection go down into the yellow field because that does contain some red and the change won't work as transparently.




Figure 20.26Figure 20.26 Step 13: In Edit Reds, move the Hue slider to -10 and you'll notice that the barn gets a new paint job.




Step 14: Notice that each time you create a new adjustment layer, your Layers palette grows toward the top. Also notice that these last three adjustment layers have mostly black Layer Mask thumbnails in the Layers palette. If you Option-click one of these Layer Mask thumbnails, you will notice that you see a mask and that mask is black everywhere except the area that was selected before you created the adjustment layer. When you create an adjustment layer when having a selection, Photoshop assumes the selection is the part you want to adjust and creates a mask that is white only in that area. Only the white parts of the masks are actually changed in color or contrast by the adjustment layer. The first three adjustment layers in the Overall Color Correction area have totally white Layer Mask thumbnails because those layers adjust the entire image. If you type a B for brush, then a D for default colors, and then pick the third brush from the top left in the Brushes palette, you can now paint 100% white over the top of the red roof on the small building at the left of the green field. This will add white into the layer mask for the Paint the Barn adjustment layer, and will make that red roof a more saturated red just as it did for the barn.

Step 15: Use Command-0 to zoom out until you can see the entire image. Now bring up the Channels palette (Shift-F10) and click on each of the Red, Green, and Blue channels, one at a time, until you find the one with the most contrast between the sky and the rest of the image. Click on the word Blue in the Blue channel and make sure the Eye icons are off for RGB, Red, and Green. The Blue channel has the most contrast in this image, so we are going to use it to create a mask separating the sky from the rest of the image. This is a useful technique that I use all the time, but it is quite often a different channel than Blue that has the most contrast. To make a copy of the Blue channel, drag the Blue channel down to the New Channel icon next to the Trash icon at the bottom of the Channels palette. You should now just be working on this grayscale channel called Blue copy, so choose Image/Adjustments/Levels and move the Input Highlight and Input Shadow sliders toward the center to increase the contrast between the sky and everything else. As you move the Input Highlight slider left, you will notice the sky being etched away. Moving the Shadow slider right makes the buildings and foreground turn towards black. An ideal mask would be a pure white sky, with everything in the foreground being pure black, then a subtle gray along the horizon, which will blend any change in the sky seamlessly into the rest of the image.

Move the Input Brightness slider, the middle one, to the left to make the transition area lighter, and to the right to darken it. Zoom into the horizon area, especially in the area of the buildings and trees, and turn the Preview button on and off to see how accurately the horizon is captured by the mask. Notice how changing the three Input sliders changes the makeup of the horizon. When you have the mask as close as possible in Levels, choose OK. Type B to get the Paintbrush, then use a large, solid brush to paint black anything that is still gray in the foreground, and paint white anything, like large dust, that is not white in the sky. The horizon line should have some gray transition values.

Command-click on the thumbnail for the Blue copy channel that you have been working on in the Channels palette. This will load the white areas of this channel as a selection. Using Command-click is the universal way to load a selection and you will find it is the easiest and most useful, so make it a point to learn. Now click on the word RGB at the top of the Channels palette and the color image should come back into display. Make sure the Paint the Barn layer is the active layer and choose Layer/New Adjustment Layer/Curves (Command-F3) to create a Curves adjustment layer you should call Darken Sky. Move the Eyedropper around in the sky while the mouse button is down and notice where the sky values are located on the curve. Click a point in the center of that sky area on the RGB curve and drag the curve down and to the right to darken the sky. Choose OK when you are happy with your darker sky. Check out the below right caption about blurring the mask! At this point, this mask of the sky is saved in the layer mask of the Darken Sky adjustment layer, so you can now drag the Blue copy channel, in the Channels palette, to the trash if you would like. Press Command-S to save your file.

Figure 20.27Figure 20.27 Step 15: Looking at the Red, Green, and Blue channels to decide which one to copy to make a mask.




Figure 20.28Figure 20.28 Step 15: Here is the setup for creating the mask for the Darken Sky layer. You are using Image/Adjustments/Levels on a copy of the Blue channel in the Channels palette. Notice the positions of the Input Shadow and Input Highlight sliders. When you think you have the mask right, turn the Preview button off and on to make sure the mask matches the horizon and you don't lose small details like the power poles you see at the top right above.




Figure 20.29Figure 20.29 Step 15: Here is the curve I used to darken my sky. After choosing OK to this Curves dialog, choose Filter/Blur/Gaussian Blur (Shift-F4) to bring up the Gaussian Blur filter. Doing a Gaussian Blur of 1 on this type of mask will usually make the transition between sky and the rest of the image a bit smoother. Zoom into 100% or 200% and notice how the telephone poles show up better after blurring the mask. Try it!




Step 16: To further modify any of your adjustment layers, double-click the Layer thumbnail of that adjustment layer and your old modifications will come up, allowing you to change them again and again without slowly destroying the integrity of the original image. One thing you should do to the Background layer, however, is use the Clone Stamp tool to remove all the spots and scratches. Click the Background layer to activate it and then use the Clone Stamp techniques you learned in the last chapter to spot this image, especially the sky. Another easier way to spot skies is to use the Dust and Scratches filter. You only want to use this filter on soft skies, and you need to use it correctly so you don't lose the grain pattern in your sky, but only the spots. Command-click on the Layer Mask thumbnail of the Darken Sky adjustment layer to reload this mask as a selection. Choose Select/Modify/Contract and use a Contraction value of 10 pixels. This moves the selection away from the horizon so the filter doesn't blur any details along the horizon. Use Command-Option-0 to zoom in to 100%, then Command-Spacebar-click to get you up to 200% while looking at the sky in the area behind the buildings. This allows you to see the details while you are working on your Background layer. Type L to get the Lasso tool and use this with the Option key down to circle and remove any selection over the power poles to the right of the buildings. We don't want this filter to run on the poles as it will think they are dust and blur them. Choose Filter/Noise/Dust & Scratches and set the Radius to 2 and the Threshold to 0. Notice that all the scratches and clumpiness in the sky is removed, but so is the natural grain pattern. The Radius is the number of pixels around a spot or scratch that Photoshop will change to get rid of the spot. Leave the Radius at 2, but increase the Threshold to around 4 or 5. Your grain pattern returns, but the large clumps, spots, and scratches are now removed. Choose Command-H to hide the selection edge and see how this sky blends with the horizon at the bottom. Turn the Preview button in the filter off and on to see the sky as it was before and after the filter. This is a good way to save time when spotting skies! You may still have to do a few large dust spots with the Rubber Stamp tool. First, do a Command-D to deselect the selection so you can work anywhere in the file. Do another Command-S to save the latest changes. This would actually be your master layers version of this image, so this is the one you would archive for future uses and different sizes. Note: My editor keeps reminding me that the Rubber Stamp tool is now called the Clone Stamp tool. I'm sure in this book you'll see it referred to as the Rubber Stamp tool a lot because I've been thinking of it with that name for over 14 years.

Figure 20.30Figure 20.30 Step 16: A safer way to run the Dust and Scratches filter is to run it on a copy of the Background layer with a layer mask to reveal the parts you want to see. That way you can always undo the effects of this filter.




Figure 20.31Figure 20.31 Step 16: The Kansas image after specific color corrections using selections and adjustment layers and before sharpening.




  • + Share This
  • 🔖 Save To Your Account