Adobe’s Smart Objects feature is something that could significantly change the way you use Photoshop. It isn’t a new feature as such, but it has been enhanced tremendously in Photoshop CS3, making it more flexible and more powerful than before.

Smart Objects are self-contained graphics that live within the regular Photoshop document as individual layers. These can be ordinary Photoshop layers that have been converted to Smart Objects or they can be content from Illustrator or InDesign that has been pasted in as Smart Objects. When a Smart Object contains vector graphics the objects remain resolution independent and scalable. Even Smart Objects created from native Photoshop text can be given effects yet remain editable. This provides the savvy user with a true resolution independent, non-destructive creative workflow, right there in Photoshop CS3.

Bringing Illustrator artwork into Photoshop as a Smart Object is simple; choose File > Place or just copy and paste from Illustrator directly. Placing creates a Smart Object automatically, but when copying and pasting artwork from Illustrator into Photoshop you’re given the choice of pasting the data as a Smart Object, as pixels, as paths, or as Shape Layers. There are times when one of the other options may be better, but for retaining Illustrator’s editing abilities the Smart Objects choice can’t be beaten. (Choosing Shape Layers or Paths converts the parts of the illustration to native Photoshop vector elements. This preserves scalability but loses any special Illustrator features, not least the ability to edit again in Illustrator, in the process.) The item appears as a new layer in the Layers panel, with a small Smart Objects badge in one corner of the thumbnail image.

These Vector Smart Object layers in Photoshop are extremely flexible. Because they contain all of the original Illustrator vector graphics, they render to the resolution of your document. This image can also be rescaled up and down without any loss of quality. With the layer selected, choose Edit > Free Transform and drag the item’s handles. You can scale the layer to any size you like, or resize the whole document for that matter, and the Smart Objects will render cleanly and crisply every time.

There are some limits to what you can do with Smart Object layers in Photoshop, all revolving around the fact that they’re not pixel-based graphics. For example, brushes, erasers, and similar tools can’t be used without rendering the layer as regular pixels first. If you really want to use these features it can be worth duplicating the Smart Object layer first in case you need to return to the editable shapes version later. Choose Layer > Duplicate Layer or Layer > Smart Objects > New Smart Object via Copy to do this, then hide one of the layers and convert the other to pixels with Layer > Smart Objects > Rasterize. But Smart Object layers can be treated with blend effects and opacity settings in the Layers panel, given layer styles, layer masks and vector masks, and adjustment layers from the Layer menu. One point to note, however, is that layer masks aren’t linked to the layer’s movement. If you set a layer mask and then move the layer itself about in the image, the mask will stay put. You’ll have to move the layer mask independently to get it into the same relative position.

Smart Filters
Using the new Smart Filters feature, Smart Objects can now also have filters applied, a Creative Suite 3 trick that takes these things to an entirely new level. In fact, for many people the Smart Filters feature is the most important new development for Smart Objects. But don’t get confused; despite the name these things aren’t different filters, they are the normal range of Photoshop filters applied to regular Smart Objects. By working in this way, filters can be applied, adjusted, and removed without any problem. This is a very different matter to applying filters to regular bitmap layers; those manipulate the pixel data itself, causing permanent changes to the image. Sure, with the History and History Brush you can do a lot to alleviate this, but it is liberating to be able to paste an Illustrator object into a Photoshop image, then apply filters and rearrange them at will at any point.

When a filter is applied to a Smart Object, look in the Layers panel to see how things are organized. A new Smart Filters sub-layer is added to the Smart Object layer, and the filter is nested as another sub-layer within that. The filter layer itself can be shown or hidden, as can the Smart Filter layer. Where this starts to get particularly exciting is when more filters are applied to the Smart Object layer. These are all added as new filter layer items within the Smart Filter layer, each with its own visibility control, and stacked on top of the previous filter. What you should try now is reordering the filters in the stack. Grab one and drag it above or below one of the other filters in the collection. The filters are calculated sequentially, so having a blur filter before or after a pointillize filter will make a big diff erent to the fi nal result. And once you’ve done this, try dragging a filter from one Smart Object to another in the Layers panel. This is just as easy and effective. About the only trick missing here is alt-dragging to duplicate the filter rather than move it.

Extracting the Original Graphics
As Photoshop doesn’t create links to source files, the Smart Object layer contains all your Illustrator drawing data. You can’t edit the paths right there in Photoshop, but you can still make all the changes you want. When you choose Layers > Smart Objects > Edit Contents or simply double-click the Vector Smart Object layer in Photoshop, a temporary file containing the Illustrator graphic will be made and opened in Illustrator. When you’ve made your changes a simple save—not ‘Save As’—will automatically update the Photoshop document’s Vector Smart Object layer. Although you didn’t import from a source document in the first place, Photoshop sets this up for you temporarily. This file will be removed automatically after you’ve saved and closed it, so you never have extra document management issues to deal with.

It is worth considering the implications of this process quite carefully, as it could prove very useful to you at some point. While you’re editing the Vector Smart Object in Illustrator you’re dealing with a regular Illustrator document, just one that exists only while you make your changes. At this point, choosing Save As from Illustrator’s File menu will save a brand new non-temporary copy of the artwork with no link to your Photoshop file and no update made to its layers. Normally this isn’t what you’d want to do, but it means you can generate a complete new Illustrator file directly from the Vector Smart Object layer in the Photoshop document—very useful if you’ve lost the original.

Further Tricks
There are other powerful Smart Object features to know about. The Export Contents command, found in Layer > Smart Objects, generates a Portable Document Format (PDF) containing the data from the selected Smart Object layer. This can be opened by Acrobat or any other PDF reader, and Illustrator can also open it as a regular editable file with all of its original attributes intact. Consider this as another way to extract a complete version of a Smart Object layer from a Photoshop document.

Replace Contents, found in the same Layers > Smart Objects set of commands, is a fairly heavy-handed way to change a Smart Object layer in a Photoshop document. Of course, if the layer has some carefully tuned transparency, blending, and Layer Style settings, it is more efficient to do this than to import a fresh layer and start all that from scratch. Choose this command; select a new Illustrator document to use instead of the current one, and you’re done.

You aren’t restricted to doing this to content that originates in Illustrator either. As I mentioned a moment ago, Smart Objects can be made from content pasted in from InDesign as well, although you’ll find that black from the standard InDesign swatch is a single-color, single-ink black, and it turns into either a single-color black when pasted into a CMYK Photoshop document or a slightly weak version of RGB black when pasted into an RGB Photoshop document. The way around this is to make yourself a rich black in the InDesign Swatches panel, one that matches the CMYK mix of the regular Photoshop black. Set Photoshop’s Foreground/Background colors in the Tools panel to black and white, then click the black swatch to see the actual ink mix in the Color Picker window. Matching this in InDesign is the simplest way to ensure a solid, perfect black matching when pasting content into Photoshop.

The fact that InDesign is a relative newcomer to the Smart Object game is given away by what happens when a Smart Object layer is double-clicked in Photoshop. Rather than opening up as a temporary InDesign document, the data is passed over to Illustrator to edit. This can lead to occasional oddities, for example strokes on text are converted to separate drawn paths, but it works very well on the whole.

If placed images are copied from InDesign or Illustrator the original resolution data is embedded. This way, high-resolution photos originally placed in a page layout can be imported to a Photoshop document and retain their full scalable resolution, even if they are used in a small, low-resolution image.

Native Photoshop layers can be turned into Smart Object layers as well. This can be done in two ways; the slightly more traditional one of choosing Layer > Smart Objects > Convert to Smart Object, and the new filter-focused route of choosing Filter > Convert for Smart Filters. Both do exactly the same job, but the Convert for Smart Filters command does pop open a window that informs the user that the layer will be converted into a Smart Object ‘re-editable smart filter’ feature. There’s obviously less call for this as the layer already exists in the Photoshop document—but being able to take advantage of Smart Filters with native Photoshop layers—applying filters without actually altering pixels in the image—is enough to win many fans. And, of course, double-clicking the layer will open it up as a separate document—inside Photoshop, as that’s the data type’s natural editor. Save changes and return to the original document to see those appear automatically.

Photoshop’s text layers can’t be edited by filters without being rasterized first, or at least that’s what most people think. Fortunately, you don’t have to give up text editability to use filters on your graphic headlines. Just convert the text layer into a Smart Object and apply the filters to that. When you want to edit the text just doubleclick its Layers panel, edit the regular text layer in the new temporary document, then save and close. Simple.

Grouping Smart Object Layers
You can group multiple Smart Object layers into one by choosing Layers > Smart Objects > Convert to Smart Object. If you want to apply settings such as Layer Styles or transform Smart Objects together this is invaluable. But although it looks like it just merges the contents of the diff erent Smart Object layers together, it actually embeds the selected layers whole and intact into a new multiple-layered Photoshop file within a single layer in the first document.

Admittedly, this can make life a little confusing, not least because the only indication that a layer isn’t a regular pixel one is the standard Smart Object badge in the corner of its thumbnail preview in the Layers palette. But it can also make things very flexible. Double-click a Smart Object layer which is actually a group and it opens the layered contents in a new temporary Photoshop document, ready for you to get creative with filters, masks, new layers, and so on. Save, and the results appear in your original file without you having to close the one you’re editing. Yes, this is the same behavior as with an Illustrator-based Smart Object. Any guesses as to what happens when you double-click a layer in this new temporary document? If it is a Smart Object layer—well, you get the picture.

In yet another interesting twist on Smart Objects in Photoshop, you can turn two or more layers of any type, not just current Smart Objects, into grouped Smart Object layers by using the same Layers > Smart Objects > Convert to Smart Object command. You are effectively embedding the selected layers as nested documents within the main file. The downside of this is that you can’t use pixel-editing tools or features on the new Smart Object even if it is made of nothing but pixel-based layers; Smart Object layers have to be opened up to be edited like that.

Smart Objects End
So why didn’t Adobe build Smart Object import support in InDesign or Illustrator? Well, as professional desktop publishing and drawing applications these have always had fairly rich features for handling artwork placed in layouts, complete with automatic updating when changes to the source files are made and saved. Smart Objects are how Adobe has managed to bring this kind of feature into Photoshop, a program that was never originally designed to do this sort of thing. This is why you bring Illustrator artwork into Photoshop as Smart Objects but simply place Photoshop images into Illustrator.

As the Creative Suite applications continue to mature, one day Smart Objects may be the term we use to describe any artwork placed, linked, or imported from one source into any diff erent destination in the Creative Suite. We will almost certainly see it make its way into some of the other programs, including Dreamweaver, although that’s not going to happen overnight. For now, remember that although you use traditional placed graphics in Illustrator and InDesign and Smart Objects in Photoshop, at the basic level the practical difference is just the terminology.

Although it took a step back in one respect with the loss of GoLive, the Smart Object feature is one of the major integration secrets of Creative Suite 3. It helps make the content you create in Illustrator or InDesign be available—and ready to be manipulated in many ways—in Photoshop, without losing the fundamental advantages of the object-oriented vector format. Smart Objects are, in effect, a way to embed one kind of file into another in such a way that you retain important characteristics of the original. This goes far beyond the basic abilities of copying and pasting or even, in certain ways, traditional placing and importing of graphics into layouts.