Ahem. (steps on soapbox) In recent times, equipment manufacturers have adopted the dubious practice of describing aspect ratios as a ratio of whole integers. Camera, display, and delivery specs regularly state ratios like 4:3, 3:2, 16:9, 17:9, 6:5, even 21:9. More recently, quite a few filmmakers have also begun adopting this habit. At the same time, there is confusion from many corners about how various aspect ratios are related and when to use them, especially when shooting with anamorphi