Smart object are like the layers in Photoshop that contain the images from the vector content like the Photoshop or the illustrator.
Sometimes editing an image would make the original image content to change. For example the image may be blurred if the size of the image is increased or decreased or the image may lose its quality if it is a high definition image. All these issues are a major concern when we upload images on the websites or use it for web based purpose.
Optimizing an image for web use is one good option before we actually include the images into our websites.
Smart Objects preserve an image’s source content with all its original characteristics that enable the editing of the layer without destroying the properties of the layer.
• Using the Smart Object you can perform transformation that are non destructive in nature i.e. the user can easily scale, rotate, distort or wrap the layer without losing the image’s original quality.
• The vector data from the illustrator is rasterized in Photoshop; to avoid this we can make use of Smart Objects.
• It is possible to edit filters applied to Smart Objects at any time.
• Edit one Smart Object and automatically update all its linked instances.
• We can try various designs with low-resolution placeholder images that we can later replace with final versions.
Linked Smart Objects
This feature was introduced in the Photoshop CC 14.2 update and made it possible to use external source files for Smart Objects. We can use an image or vector file in several Photoshop documents as a Linked Smart Object.
If you modify the original object later on, it will automatically update in all of your PSD files i.e. edit one Smart Object and automatically update all its linked instances.
Another advantage to Linked Smart Objects is that they won't increase your Photoshop document's file size.
Thus Smart Objects are an incredibly powerful tool in Photoshop. They can be used to speed up your workflow but also to retain the quality of your images, and reduce file size.