This week I was asked a question for which I had tried and failed to provide a satisfactory answer 50 years ago.
The first occasion was when I was a teenager working in a camera shop. After having half a century to think about it, I believe I came up with a more comprehensive, albeit more confusing, answer this time.
On that first occasion, a customer had used his 35mm camera to take a group shot of 15 family members standing shoulder to shoulder. When the film was developed and printed on 3½” x 5” paper, all 15 of the subjects were in the frame. When he then ordered an 8 x 10 inch enlargement, it came back missing two parents on the left and two cousins on the right. That was when I tried to explain the concept of aspect ratio.
Aspect ratio is a number that encompasses the proportional relationship between width and height. 1:1 (read “one to one”) is square; 3:2 aspect ratio is used by most 35mm cameras, meaning that the pictures are rectangular—three units wide for every two units tall.
The problem my customer encountered is that the 3:2 aspect ratio of his camera was a wider rectangle than the 8x10 enlargement, resulting in cutting off four of his relatives. I offered to reprint his order as a wider 8” x 12” rectangle to include all 15 people, but NO! He had already purchased a picture frame 8” x 10” so he wanted me to defy the laws of physics by printing a 4:6 ratio picture to fit his 4:5 ratio picture frame.