Put all the images into a zip file (this is the format used by a lot of image viewers).

There are many comic / magazine viewers which take a cbz, cbr file (renamed zip file, and renamed rar file). These are much faster to load than a PDF and are great for use on a laptop. You just need the pages to be named in order, so rather than 1.jpg, 2.jpg it is better to use 001.jpg, 002.jpg etc.