I find its a loose term on these forums. I\'ve seen a few different photos claiming to be a 50% crop, but it just didn\'t look right. Where as a 100% crop is just a crop of any given photo, shown completely. For instance you zoom in 100% on any given photo, you highlight 500x500px, and when displayed, it takes up 500x500px on your screen. But as for your exactly, you seem to have the right idea.