Resizing Images allows you to change the photo size to dynamically fit the print media better (or the resolution so the printer can print it(dpi)) or the changing the size of the image to reduce the file size. Resizing images can also be important for when working online to prevent other users from stealing work you have produced whatever the reason is important to know how to resize an image in your preferred photo editor.
Once you have finished editing the image, you will need to resize the image to postcard size. Most likely the camera file will not fit the specified size for the post card. To do this we need to click Image and then Image size.
After this a small pop-up window will appear, allowing you to specify the size and resolution of the image.
For a postcard we need to specify a height and width of 10x15cm (this will depend if the image is horizontal or vertical) But the image resolution will need to be 300, this is due to the printer, can only print at 300dpi and this is also known as the industry standard for resolution on printers.
I will then confirm this and then the image will be resized.
Image resizing is not a hard task to accomplish but it is knowing when it is suitable to do and how you should apply it. If you were wondering I have Photoshop CS5 but this is the same process on Photoshop CS6 and Photoshop CC, it probably is the same for older versions but I might be wrong.