CHOOSE YOUR IMAGE SIZE AND FILE FORMAT

6. CHOOSE YOUR IMAGE SIZE AND FILE FORMAT

ONCE YOU’RE DONE working with your images, you’re going to want to save these files in a format that either lets you make changes later or that you can share with other people, be it in print or on the web.

There are two general file formats that you will be working with most of the time. The Photoshop (PSD) file format retains all of the work that you have done to the file in Photoshop. This is largely considered to be a layered file format (we’ll talk about layers a little bit later). Use this format to save any kind of work that you may want to revisit later.

The second format that you will largely work with is the JPG format. This is the format used for printing images and sharing them online. The file is generally smaller than a PSD file because there is a certain amount of compression applied to make the transmission of the file easier. The level of compression is largely dependent on what you specify.

When you select the JPG format from the File > Save As dialog box and click Save, you’ll be presented with a JPG Options dialog box (Figure 6.1). This is where you can designate the quality at which you want to save the file. A higher Quality number means less compression is applied to the file. A lower Quality number means more compression is applied to the file. While you won’t necessarily see the difference until you really zoom into the file, there is a drastic difference in file size (Figure 6.2).

Figure 6.1 The JPG Options dialog box asks you to specify the quality at which you want to save your file. If you select a higher quality, less compression will be applied to the file.

It’s often a good idea to select a lower quality (higher compression) when you want to share an image online or send it via email, but if you want to retain as much detail as possible, it’s better to choose a higher quality (less compression).

It’s also important to know how to resize an image while you’re working with it. For an image you want to share on the Internet, you generally do not need a resolution higher than 72 pixels per inch. With the file open, select Image > Image Size, and then adjust the Resolution right in the Image Size dialog box (Figure 6.3). I recommend you change the resolution before you change the width and the height of the document you want to resize.

If I want to share a photograph online—on Facebook or Instagram, for example—I generally set the longest side to no more than 1600 pixels and choose a resolution of 72 pixels per inch. I usually save the document with a Quality of about 8. That gives me a good balance between quality and a small enough file size to share online.

Figure 6.2 Lower quality means more compression and much smaller files. I chose a Quality of 0 for the file on the left, which resulted in a file size of 599 KB. The file on the right was saved at a Quality of 10 and is 9.1 MB.

Figure 6.3 For images you plan to share online, a resolution of 72 pixels per inch works well.