Adobe Photoshop CS5 for Photographers - Martin Evening [194]
Freeze mask tool (F)
Protects areas of the image. Frozen portions are indicated by a quick mask type overlay. These areas are protected from any further liquify distortions.
Thaw mask tool (D)
Selectively or wholly erases the freeze tool area.
Hand tool (H)
For scrolling the preview image.
Zoom tool (Z)
Used for zooming in or zooming out.
Basically, you select one or more of the Liquify tools to manipulate the image shown in the preview area and when you are happy with your liquify work, click or to OK the pixel manipulation. Photoshop then calculates and applies the liquify adjustment to the selected image area.
The Liquify tools are all explained in the column on the left and the images shown in Figure 8.12 visually summarize the effect each of these tools can have on an image. The easiest of these to get to grips with is the warp tool, which allows you to simply click and drag to push the pixels in the direction you want them to go in. However, I also like working with the push left tool, because it lets me carry out some quite bold warp adjustments. Note that when you drag with the push left tool it shifts the pixels 90 ° to the left of the direction you are dragging in and when you drag with the tool, it shifts the pixels 90 ° to the right.
Figure 8.12 These illustrations give you an idea of the range of distortion effects that can be achieved using the Liquify tools described on page 442.
The pucker tool is sometimes useful for correcting over-distorted areas and squeezing the pixels inwards again. The mirror tool is perhaps the most unwieldy of all, as it copies pixels from 90 ° to the direction you are dragging, and therefore acts like an inverting lens, which if you are not careful can easily rip an image apart. Apparently, retouchers who work on adult magazines are fond of working with the turbulence tool. This is for reasons I have yet to fathom and it is probably inappropriate for me to enquire further! The key to working successfully with the Liquify filter is to use gradual brush movements in order to build up the distortion in stages.
Liquify tool controls
Once you have selected a tool to work with you will want to check out the associated tool options which are shown in Figure 8.13. All the tools (apart from the hand and zoom tool) are displayed as a circular cursor with a cross-hair in the middle. The tool options are applied universally to all the tools and these include: Brush Size, Brush Density, Brush Pressure and Brush Rate. If you mouse down on the double-arrow icon next to the field entry box, this pops a dynamic slider which can be used to adjust the settings. You can also use the square bracket keys to enlarge or reduce the tool cursor size, and the rate of increase/decrease can be accelerated by holding down the key. I highly recommend that you use a pressure sensitive pen and pad such as the Wacom™ system and if you do so, make sure that the Stylus Pressure option is checked and set the brush pressure to around 10–20%. Note that the Turbulent Jitter control is only active when the turbulence tool is selected. In this context the jitter refers to the amount of randomness that is introduced to a turbulence distortion applied with this tool.
Figure 8.13 This shows the Liquify dialog options. The Reconstruct Options are shown circled here in green.
Reconstructions
Next we have the Reconstruct Options, of which the default mode is set to ‘Revert’. If you apply a Liquify distortion and click on the Reconstruct button, the image will be restored to its undistorted state in gradual stages each time you click the button (while preserving any areas that have been frozen with the freeze tool). If you click on the ‘Restore All’ button the entire image is restored in one step (ignoring any frozen areas). The default Revert mode produces scaled reversions that return you to the original image state in the preview window. However, there are some alternative options which are more relevant once you have created a frozen area. For example,