These are common questions among beginners who are just learning to use Photoshop. Many who are just learning to use Adobe Photoshop often are confused by the differences in the canvas size and image size functions.
The ability to adjust the canvas size is just one of the many features available in Adobe Photoshop that puts the user in control of every aspect of the digital image editing process.
While there is much more too it, changing the canvas size essentially creates more work space by adding extra pixels to the total image. There are many ways you can use the canvas and image size functions to make your digital image editing work easier.
Not only can you change the size of the canvas but you can also change the canvas color. This function can be used to create frames or borders around your images. In addition, there are many other more advanced techniques for using the canvas size and image size functions.
As with all of the features and functions of Photoshop, the most important thing to keep in mind is that you take the time to learn how to properly use Photoshop's image and canvas size functions before you jump into a photo-editing project.
Photoshop is not nearly as difficult to learn as many might think but it does require that you learn proper techniques. While with many lesser quality photo editing programs you can sometimes get by with trial and error, Photoshop is not that easy to just jump in and create professional quality graphic work without some knowledge.
With that being said, once you learn Photoshop there will be no limitations to what you can create.
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