Ever since their introduction in Photoshop CS2, Smart Objects have rapidly become one of the most useful aspects of Photoshop. Smart Objects allow you to work with image data non-destructively, which means that it’s always possible to adjust your edits at a later date without sacrificing any image quality.
We often hear about using ‘best practices’ in our digital workflows, but Smart Objects are a best practice that really pays off, and they’re fairly simple to learn and use.
(Note: we are using Photoshop CS5 on Windows 7 for the screenshots in this introduction, so your interface may look slightly different. The general principles remain the same.)
In Photoshop files, there are two ways that image data can be represented: as pixel (raster) data or as vector data. Pixel data is stored as a bitmap, meaning that there is information describing colour and luminosity for each and every pixel of your image.
Vectors, on the other hand, are actually mathematical formula that describes the anchor points, lines and curves for each shape as well as data about how each area is coloured.
When you’re working with vector data such as shape layers or vector masks, the visual information is simply mathematics, so it can be scaled, shrunk, distorted and otherwise changed as many times as you want without losing any visual information. This is what we mean by ‘non-destructive editing’. On the other hand, if you shrink a rasterized image, distort it, and then scale it back up again, all you’ll wind up with is a blurry mess because the pixel data was permanently changed each time you applied an edit.
Enter Smart Objects to save the day!
Smart Objects are layers that can contain either raster or vector data, and they allow you to edit both types of image data non-destructively. This is a huge benefit when you’re not sure exactly how your final image will look, and you want to retain the ability to adjust things later without having to repeat every single step or rely on the History panel.
To get started with Smart Objects, open up any of your Photoshop documents where you’ve done some retouching or editing on a new layer.
(Note: Whenever you do retouching work, you should always be working non-destructively, even for things like clone stamping. You just create a new layer, set the clone stamp tool to sample layers ‘Current and Below’, and do all your edits on that new layer.)
It is possible to convert any of your existing raster image layers into Smart Object layers by simply right-clicking on the appropriate layer in the Layers palette and choosing ‘Convert to Smart Object’. Once your layer has been converted to a smart object, it will be identified by a small icon in the bottom right corner of the layer thumbnail, as you can see here. Once your edit is a Smart Object, you can use all sorts of transform tools on it to ensure you’re getting the right effect without damaging the original.
Another great feature of Smart Objects is the ability to use Smart Filters. While it can make you seem like a bit of an amateur to go overboard with the Filters section of Photoshop (don’t worry, we all experimented like this when we were still learning 😉 ), there are a few that are extremely useful. Sharpening filters are a great example, and since the filter is applied non-destructively, you can take your time to decide just what degree of sharpening is appropriate for the final image.
Often it’s necessary to sharpen your retouching layers a bit differently from your final overall image to ensure they blend properly, and with Smart Filters you can always edit the results later. Additionally, you can apply a layer mask to the actual filter itself, allowing you to control which areas of the image are affected by the Smart Filter.
The only downside to using Smart Objects is that you may have to alter your workflow a bit, since you can’t use any tools that actually alter the pixel data itself, such as cloning, painting, dodging or burning.
For dodging and burning, it’s possible to create the same effect using a separate layer with a mask and the appropriate Blending Effect setting. A better idea is to get comfortable using Curves adjustment layers and layer masks, which allow you an even greater degree of control over the results of your edits while staying non-destructive.
One of the most interesting new features in Photoshop CC is the ability to incorporate Linked Smart Objects in your Photoshop files. This is a bit tricky to explain but it can be a great timesaver, so bear with us.
Linked Smart Objects appear visually in your image, but they don’t actually exist within your document – they just link to an external file. You can link to the same external file from multiple Photoshop documents, which has a number of uses for photographers.
For example, say you want to add a watermark to all of the images that you post on the internet (always a wise decision). You create a new Photoshop file that contains your watermark on a transparent background, and save it.
Then you can add that file as Linked Smart Object in all the images you want to post – and if you decide halfway through that you want to change how your watermark looks, that’s no problem! Instead of having to go back and edit every file one by one, you can simply edit the original watermark file, and the Linked Smart Object will update automatically in every document that it is linked to.
Now that you’ve got a handle on the basics of Smart Objects, it’s time to go out and put your knowledge to use in your workflow! It might take a little bit of time to get the hang of them, but they’re worth the effort for the added flexibility they bring. Once you get used to them, you’ll wonder how you ever managed to live without them.