Photoshop is a fantastic tool, but it is not always the fastest software on earth. Large files such as PSD, TIFF, and PSB that contain numerous layers can require a few seconds, if not minutes, to load. When all you want to do is quickly check that all the files in a folder are the final versions, it can be tedious! However, there is a neat trick to open your big files much faster. Here is how.
Let’s start by opening up Photoshop and going to the File menu to select "Open"; alternatively, you can press Command/Ctrl+O. You should now have something like this on your screen:
Browse through your files and find the picture you wish to open. Select only one at a time because this technique won’t work when loading multiple images at once. When your file is selected, press and hold Alt/Option+Shift while clicking on the Open button.
If you have done everything right so far, meaning you kept Alt/Option+Shift down while clicking Open, the window above should be displayed. Press "OK," and within seconds, you will have a flattened version of your file ready to use in Photoshop.
As you can notice, my file contains only one layer, the background and weighs about 285 MB instead of its original whopping 1.28 GB. That’s it! Nothing very complicated here; all you have to remember is to press and hold Alt/Option+Shift while opening your file from the menu in Photoshop. Also, keep in mind it only works if you select one picture at a time. Finally, one word of caution: if you edit the flattened version and save the changes, it will override the original PSD, PSB, or TIFF file. So, be sure to use this trick only for files you do not wish to further retouch or for files that do not need to have their layers saved.