What it does

Montage composites multiple images into a single, larger image. You may need to resize large images before you attempt to montage them.

The width parameter controls how many images wide the montage will be. With a width of 4, and 8 images selected, you will get 2 rows of 4 images. If you have 6 images selected, the first row will have 4 images, and the second will only have two.