OM Studio Photography — Studio portrait | omstudiophotography.com
Every common portrait ratio with its stop value, the look it produces, and the fill-power setting that hits it.
A key-to-fill ratio compares the bright side of the face with the shadow side. Meter toward the key from the subject's position, then toward the fill; the difference in stops is the ratio. One stop reads as 2:1, two stops as 4:1, three stops as 8:1.
2:1 — a 1-stop gap — is the soft commercial look: shadows are lifted but still present, skin tones stay even, and the picture retouches easily. It suits beauty, corporate and family work where nothing should look harsh.
3:1 — about 1.6 stops — is the classic portrait ratio. The shadow side is clearly darker but detail holds, giving the face modelling without drama. When in doubt, start here.
On narrow screens, swipe or scroll the plate sideways.
4:1 — 2 stops — turns dramatic: the far cheek goes deep and the light describes bone structure. 8:1 — 3 stops — is low key, where the fill side nearly vanishes and the picture lives on the key side alone.
To set a ratio, meter the key alone first and note the aperture. Switch the key off, meter the fill alone, and lower its power until it reads the required number of stops under — most heads give 4–5 stops of range down to 1/16 or 1/32, so the power knob is enough. Switch both lights on and re-meter the key side for the working aperture.
Camera settings do not change with ratio: ISO 100, shutter at or under the 1/160–1/250 s sync limit, white balance at 5,500–5,600 K. Only the fill's power moves. For the placement that feeds these numbers, see the Three-Point Studio Lighting Setup page.
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