[5-27] “Aspect ratios”

Photography starts with a composition dictated by the photographer’s camera; the sensor is either a square or some kind of rectangle.

Common aspect ratios:
2x3 – generic 35mm (0.67:1)
4x5 – large-format cameras (sheets of 4x5”, 8x10” film) (0.8:1)
1x1 – square (Rolleiflex medium-format)
9x16 – smartphones (0.56:1)

Less common:
6x7 – pseudo-square (including Mamiya 7ii, rz67) (0.86:1)
3x4 – three-quarters (Micro Four Thirds, Mamiya 645, historically used by painters) (0.75:1)

Some observations:
• Modern full-frame sensors come with a 24x36mm sensor (2x3); the cropper sensors preserve this ratio; this comes from a lineage of 35mm film and the images tend to be wide
• Richard Avedon’s portraits demonstrate the useful and unique characteristics of 4x5
• Squares were popularized by Instagram (which now it permits a wider range)
• Aspect ratio can be adjusted, by cropping an image (losing pixels) or creating new pixels (image generation)

In cinema:
• American widescreen (1.85:1)
• Anamorphic (2.35:1)

In the early years, I took most portraits in the vertical format using a 2x3 aspect ratio (D610). The images always felt a bit tall; often I’d crop the long edge for to fit closer to 5x7 or square.

I now prefer to ask or consider the final composition. Most profile pictures (e.g. ig, Linkedin) require a square (then cropped into a circle). The size of the image also should inform how the picture should be taken.