Adobe Photoshop CS5 for Photographers - Martin Evening [108]
Undoing and erasing brush strokes
As you work with the adjustment brush, you can undo a brush stroke or series of strokes using the Undo command ( )
Previewing the mask more clearly
Sometimes it is useful to initially adjust the settings to apply a stronger effect than is desired. This lets you judge the effectiveness of your masking more clearly. You can then reduce the effect settings to reach the desired strength for the brush strokes.
Resetting the sliders
Double-clicking a slider name resets it to zero, or to its default value.
Previewing the brush stroke areas
If you click on the ‘Show Mask’ option, you'll see a temporary overlay view of the painted regions ( Figure 3.70 ). The color overlay represents the areas that have been painted and can also be seen as you roll the cursor over a pin marker.
Figure 3.70 In this screen view, the ‘Show Mask’ option is checked and you can see an overlay mask for the selected brush group. Click on the swatch next to it if you wish to choose a different color for the overlay display.
1.
Here is a portrait of Rod Wynne-Powell who tech-edited the book for me. To add a new adjustment brush group, I adjusted the effect sliders, clicked on the image and started painting. In this first step I applied a darkening effect to the background.
2.
I then added further brush groups. In this step I added a new brush group to lighten Rod's forehead.
Auto masking
At the bottom of the Adjustment Brush panel is the Auto Mask option and when this is switched on it cleverly masks the image at the same time as you paint. It does this by analyzing the colors in the image where you first click and then proceeds to apply the effect only to those areas with the same matching tone and color ( Figure 3.71 ). It does this on a contiguous selection basis. For example, in the steps shown here, I dragged with the adjustment brush in Auto Mask mode around the outside of the basket handle to darken the outer area and then dragged separately on the inside of the basket handle to include this in the auto mask brush group. While the Auto Mask can do a great job at auto-selecting the areas you want to paint, at extremes it can lead to ugly ‘dissolved pixel’ edges. This doesn't happen with every photo, but it's something to be aware of. The other thing to watch out for is a slow-down in brush performance. As you add extra brush stroke groups, the Camera Raw processing takes a knock anyway, but it gets even worse when you apply a lot of auto mask brushing. It is therefore a good idea to restrict the number of adjustment groups to a minimum.
Figure 3.71 Quite often, all you need to do is to click on an area of a picture with the color you wish to target and drag the adjustment brush in Auto Mask mode to quickly adjust areas of the picture that share the same tone and color.
1.
This shows the original photograph of a basket of oranges against a stone wall, shown here with just the Basic panel corrections applied.
2.
I selected the adjustment brush and clicked on the minus Exposure button to set this to −0.50, then dragged the Saturation slider to +40, chose a blue paint color and started painting the wall. Because ‘Auto Mask’ was checked, the brush effect only adjusted the wall.
3.
To demonstrate how effective the auto masking was in this image, I lowered the Exposure slider to −2.00, which darkened the wall even further. You can see how the basket handle and fruit stood out more as I did this.
Hand-coloring in Color mode
The adjustment brush tool can also be used to tint black and white images and this is a technique that works well with any raw, JPEG or TIFF image that is in color. This is because the auto mask feature can be used to help guide the adjustment brush to colorize regional areas that share the same tone and color. In other words, if the underlying image is in color,