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About the Author
Alex Walker
Alex manages design and front end development for SitePoint.com and writes SitePoint's monthly design newsletter, the SitePoint Design View. He also maintains Pixel Perfect, SitePoint's Web Design Blog.
3 Cool Tricks You Can Only Do In Photoshop CS4
I have to admit it crossed my mind. The new Photoshop arrived and I found myself thinking: "Ah, come on, the old bird must be into her twelfth version by now. That's like 125 in dog years, isn't it? Surely after all this time the well has run dry and she has nought but gimmicks and parlor tricks to try to lure me in this time?"
While that may have been how I went in, I'm pleased to report she still has the ability to surprise and please.
Let's take a closer look.
Content Aware Image Resizing
This is a nice story for Adobe. In August, 2007 there was a ripple of excitement through the graphics community when Shai Avidan and Ariel Shamir demonstrated a new mathematical approach to image resizing—dubbed Content Aware Image Resizing (CAIR). Adobe were quick to recognize the opportunity and immediately added Shai to the Photoshop team. However, finding a good idea and integrating it into a Goliath-like Photoshop are quite different things, and many a "gee whiz, ain't that cool" idea has been warehoused when it all became too hard to make it work in the big wide world. Thankfully that hasn't happened with CAIR, and Adobe have shown some commendable adaptability in the smooth integration of CAIR technology into Photoshop CS4.
If you missed the initial talk on CAIR, it's a fascinating concept. Traditional image-scaling methods stretch and compress all parts of the image equally, with scant regard for the image content. As the example below shows, this gives you nasty and very noticeable image distortion in all but the smallest resizes.
CAIR takes a smarter approach. As the name suggests, Content Aware Image Resizing analyzes the content of your image and then limits all image adjustment to the areas of least visual importance.
For instance, in the example below you can see the application is making its biggest changes to the more nondescript parts of the wall and doors, leaving the important compositional elements (Obama, the switches and bins) virtually untouched.
Adobe's implementation of CAIR is very slick. While some early versions relied on the user cutting marks to protect detail, Photoshop CS4 generally gives you a great result by simply switching on the "Protect Skin Tones" option.
In short, this is one of those rare occasions where you have a new feature that has a serious wow factor and is seriously useful from day one. It's a while since I can remember generating a crowd at my desk while demo-ing a new Adobe feature, but CAIR was able to do that. While it's true that some images will lend themselves to CAIR more than others, I think this is genuinely a killer feature for almost any regular Photoshop user.
Adjustment Layers
Adjustments layers are nothing new, but they've become more powerful and easier to control in CS4.
The first thing you'll notice is that they've been given their own dedicated palette, giving you a fast, one-button click method to apply levels, curves, saturations, and color balances, amongst other adjustments. Clicking a button launches a hidden control subpanel for the adjustment, rather than the traditional popup dialog. This felt a bit weird to me. I suspect you adapt to it quickly, but I can't think of another place where they handle the UI this way (the graphic below illustrates this idea).
Now, obviously curves have been around forever, but the way they can be applied here is new and, I think, rather cool—the On-screen Adjustment tool. Let's look at a quick example of it in action.
