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Photoshop 7 Arrives for Mac OS X
Pages: 1, 2

New Levels of Color

In addition to the new functions in Photoshop 7.0, Adobe enhanced a few of its more traditional ones. Auto Color is a new panel in the Adjustments submenu under the Image menu, designed to remove unpleasant casts created by scanners and digital cameras. Like the Auto Levels command, it looks for the darkest and lightest points in the image, and balances out the colors, but it also forces the midpoint to a neutral gray, for more natural-looking photographic images.



You can make further refinements from the new Levels panel. There’s a new Options button, which brings up three algorithm choices. If these seem frighteningly unfamiliar to you, know that they’re old friends in slightly new garments. “Enhance Monochromatic Contrast” is the same as Auto Contrast; “Enhance Per Channel Contrast” is the same as Auto Levels (which performs a contrast adjustment individually for the Red, Blue, and Green channels); and “Find Dark & Light Colors” is the same as Auto Contrast, except that it uses color information in addition to light and dark values. With the “Snap Neutral Midtones” option selected below, the “Find Dark and Light Colors” algorithm performs the same function as the Auto Color command, but notice that you can select the “Snap Neutral Midtones” option for each of the three algorithms, for a variety of additional effects.

So why am I going into all this? Because although the Auto Color command is a highly useful tool, you’ll find that depending on the file you're working on, you might get better results using another tool. It’s best to experiment, and it’s not too painful.

Let me show you an example using a digital photograph of a painting composed only of red, white, and blue paint on brown postal paper. Notice how the original has that greenish pall that sometimes characterizes digital photos. (The blues and reds should look much more “primary.”) After running the Auto Color command, the greenish tint is gone, and the colors are much more true.

Without adjustment With adjustment
Using the auto color command in Photoshop allows you to make quick color adjustments.

Out of curiosity, I also ran the Auto Levels command, and got a very similar result. However, after using both automated controls, I felt that the images had a bit too much contrast, to the point where the white areas were burned through to “empty-file” white, and the colors are a bit on the lurid side. So, using the Levels panel, I was manually selected the dark and white points using the eyedropper tool, and got much better results. Ironically, I found that I got the best results of all without using any of the automated controls, and it was also extremely simple.

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New Web Capabilities

The Save for Web dialog box has also been spruced up quite a bit. Now with one click of the Eyedropper, you can specify which colors are transparent, or swap out one color for another. Also, a new Dithered Transparency option lets you create a simple drop-shadow effect that looks great on the Web, over any background. Designers no longer have to resort to the clever but time-consuming trick of creating a logo over a copy of the existing background, to make it blend in. For further refinements while saving a file for the Web, you can choose to assign a greater number of colors to specific text layers or vector images, if you’d prefer to sacrifice a bit of quality from the rest of the image.

All of the enhancements to Save for Web in Photoshop were also made in ImageReady, but ImageReady has had a few new additions of its own. A new Rollover palette lets you more quickly and easily create and monitor rollover states, to create highly interactive graphics without learning JavaScript. Along with the usual Over and Down states, you can designate a layer as a variety of other states, including Selected, so it remains in view until the user clicks on something else. That way, you can create an interactive, multi-message page using only one graphic.

ImageReady’s new Variables feature lets you create single Photoshop files with data sets: images and text that change with a click. This allows you to easily save out different optimized versions of your file, with slightly different content. Interestingly, if you opened the same multi-data-set file using Photoshop, you’d only see one of the versions; ImageReady alone has the capability of viewing data sets in a Photoshop file.

Extra Goodies

Adobe has also added three tools to the Filters menu. The Extract and Liquify filters resided in the Image menu of Photoshop 6.0, and in the process, Liquify was significantly revamped. The Pattern Maker is a new addtion, and this is the tool we used to create the desk pattern above. The Extract filter is designed to help you remove an object from its background. Using a combination of the Magic Wand and the Magnetic Lasso to do this is a time-consuming, headache-inducing task. Extract lets you use relatively “blunt” tools to define your object, and then figures out how to define the edge, tricky and shadowy as it might be, on its own.

Using it to extract this rose from its background, and place it against a different sky, my first result left a little to be desired. [middle image] I had very quickly defined the edge, and applied the filter after having put in very little effort, and it shows. I then took a deep breath and tried again, using the Smart Highlight to help me define the edge, and using the Edge Restore and Cleanup Tools to help tighten things up a bit before I applied the filter. [right image]

Rose 1 Rose 2 Rose 3
Extracting a rose from the original shot (left) by using the extract tool without adjustments (middle) yielding acceptable results. Better results were achieved by also using smart highlight and edge restore (right).

I spent about 10 minutes on this, and if I were using the selection tools, it would have taken me a good half-hour, and would have resulted in a few gray hairs. Notice that there are still a few imperfections, but with a little extra time, the filter could provide better results. Extracting a person from a background is considerably more difficult, especially if they have hair that’s blowing in the wind, but again, it can be done, and it will easier than using a complicated array of selections.

The Liquefy filter provides some interesting distortion effects using 3D meshes, which are like very simple wireframes. And the new version allows you to work in a low-resolution preview mode, since you can save meshes and apply them to high-resolution images. Imagine placing your image on a tablecloth with a grid pattern, and imagine wrinkling and twisting the cloth to create distortions. It’s a powerful, flexible filter, with plenty of tools and options. You can “freeze” areas to keep them from distorting, and “thaw” them to free them up again. At any point you can wave a Reconstruct tool over an area to return it to normal, or revert the entire image. You can also change the size and “strength” of the distorting brush, i.e., how much pressure will be exerted on the grid.

The Pattern Maker generates patterns from selected areas of your images. So you can, for example, select a bit of grass from an image, generate a pattern from it, save the new pattern, and then use it just as you would any other pattern. The Pattern Maker slices and dices your selection when it generates the pattern, so that it has an organic, non-repetitive feel.

Just for fun, I took this same picture of a flower and created a pattern using the grass. I then painted grass back into the picture using the Pattern stamp tool. As you can see, although it looks odd, the effect is fairly organic.

Background
You can generate organic looking backgrounds with the pattern maker in Photoshop 7.

But if you look closely, you’ll see the places where the original selection was chopped up to make the pattern. However, as we saw above, if you use this tool to make a pattern from a small, uniform area, to be used with the Healing Brush or Patch Tool, it becomes extremely powerful.

I’ve got one small gripe with the Pattern Maker: After you generate a pattern using a selected portion of your image, save the pattern, and click OK, your entire original will turn into your new pattern. So after you save a pattern, you have to hit “Cancel,” which is a bit clunky. It would be better if the panel had a button that said something like “Return,” or if when you clicked OK it placed your pattern in a new layer and left your original untouched.

Final Thoughts

The big news is, Photoshop is now on Mac OS X. But beyond that, is it worth the upgrade? The answer is, most certainly yes. Though the new automated tools won’t provide instant solutions to every problem, in general, Photoshop 7.0’s diverse enhancements is well worth the price of admission.

David Weiss is an Oakland, California based freelance writer. He's worked as a senior editor at Macworld magazine, and as the lead editor of MacHome Journal. Read more about David at www.davidweiss.net.


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