Portrait Distance: What Focal Length at What Range

Longer lenses do not "compress" faces. Distance does. A longer lens makes you stand further back to get the same framing, and it is the standing further back that flattens the perspective. Get that straight and most of the confusion about portrait lenses goes away.

Why distance matters, in numbers

The tip of a nose sits about 12 cm in front of the ears. Because things look larger the closer they are, the nose appears bigger than it should relative to the ears by roughly 12 cm divided by your distance. At 0.5 m that is about 24 percent, which the eye reads as a big nose. At 1 m it is about 12 percent, at 2 m about 6 percent, and at 4 m about 3 percent. Nothing about the lens enters into it. If you photograph from 1 m with a 50 mm lens and crop to what a 100 mm would have framed from the same spot, the face shape is identical.

Focal length matters only because it decides how far you must stand to fill the frame. Stand where you want to stand, then pick the lens that frames the shot from there. Too wide? You can crop, and the perspective will not change.

How far to stand

Distance is focal length times the actual height you want in the frame, divided by the sensor's height. On full frame in portrait orientation (the long side vertical, 36 mm), that gives these working distances for three common framings: a tight head shot (about 40 cm of height), head and shoulders (70 cm) and waist up (1.2 m). If you shoot in landscape orientation, the frame is only 24 mm tall, so multiply the distances by about 1.5.

These depend on how tight you frame, so treat them as starting points. The calculator on this site works backwards from a photo you already have: measure the subject's height in the frame, and it tells you how far away you were.

What each focal length is like

At 35 mm you are close enough to talk without raising your voice, and the background stays in the picture. It suits environmental portraits and documentary work, but under about 0.7 m the nose and forehead start to stretch, so stay with half-length frames. At 50 mm, a head-and-shoulders portrait is shot from about a metre, and faces look much as they do in person, neither flattened nor stretched. It is the most forgiving of the lot.

At 85 mm the distance is about 1.7 m for head and shoulders. The nose-to-ear difference has fallen to around 7 percent, which is why 85 mm has been the default portrait lens for decades. It is also close enough to talk to your subject. The 100 to 105 mm macros are a close cousin: stand a little further back, and the same lens can handle detail shots. At 135 mm you are 2.5 to 4.5 m away, the faces are flatter still and backgrounds melt away, but you have to have the room, and directing someone across a room is harder than it sounds. At 200 mm you are 4 m or more away, which suits candids and nervous subjects, and the longer distance often makes people relax.

APS-C and Micro Four Thirds

Distances depend on the field of view, not on the sensor. A 56 mm lens on APS-C frames like an 85 mm on full frame, so you stand in the same place and get the same perspective. If you put an 85 mm lens on an APS-C body instead, you crop in and will need to stand about 1.5 times further back for the same framing. That gives flatter perspective but needs more room. On Micro Four Thirds, a 42 mm lens frames like an 85 mm on full frame.

Will it fit in the room?

A bedroom or small studio with about 3 m of depth works with 35 mm or 50 mm and struggles with 85 mm. Five or six metres gives you 85 mm comfortably and 100 mm at a push. With 8 m or more, 135 mm is practical, and outdoors you can use whatever you like. If the room will not let you stand far enough back, that is the constraint, and zooming out will not get you the look of a longer lens from further back. The perspective is set by where you stand.

The background comes into it too

A longer lens from further back gives a stronger blur on a background the same distance behind your subject, and it makes that background look larger and closer, which is the "compression" people talk about. A 50 mm shot from 1 m shows more of the surroundings and less blur. The two are different looks rather than better and worse, and the blur side is covered in the bokeh guide. If you are choosing an aperture, the portrait aperture guide is the companion piece.

The same distance logic applies to other subjects, as in the posts on newborns, pets and gym photography. A 50 mm at 1.5 m and a 135 mm at 4 m can both make a good portrait. They just feel different.