Several factors can effect the height of objects (or people) in photos. Not only do we have posture and footwear differences to consider, we also have other factors such as whether the camera is tilted, how high the camera is above the ground, and the position of the subjects in the frame.
A plain background makes it harder to decipher if these factors might be present.
Not all photographers are going to hold their camera perpendicular to the ground. This photo below shows how a 4 or 8 degree tilt might effect height. You could easily reduce the height difference between subjects by 1-1.25 inches with a 4-5 degree tilt or 2-2.25 inches with a 7-8 degree tilt.
Camera Horizontal / 4 degree tilt / 8 degree tilt
If the backdrop was neutral with no objects present, it may be harder to tell how much tilt there might be in a photo.
8 degree tilt Reducing Height Difference
In many photoshoots, the camera is pretty level, but there will be a proportion which might have 1-2 degree tilts that could effect either side of the photo.
For instance, a small tilt can knock a half inch off one side easily.
The right photo below is the original, but I felt there was a 1-2 degree tilt against Alexis, so the left is closer to being an accurate representation.
1.5 degree tilt
Distance of Subjects
The closer the camera is to the subjects, the greater the effect might be in making one person appear taller than they really are. But sometimes being closer or slightly further away might not have much effect. In fact, the height of the camera plays a role in this.
For instance, using these bottles to illustrate: On the photo on the right, we have lowered the camera a few inches, thus making the top of the right-hand bottle appear shorter against the left-hand bottle. In the photo on the left, I put the camera at the same height as the black mark.
Camera Height can effect Real Height Difference
In this photo below, being noticeably closer (8-9 inches) can certainly make the person closest to the camera appear 2-3 inches taller than they are.
Jenny with significant Camera Advantage
If we have a camera that is positioned higher up, sometimes the person further away can be the one who appears slightly taller (the person closer to the camera is now at the disadvantage). For instance, in this still from my video called Sly Photo Tips
, I placed the camera higher up and was standing a few inches behind Jenny. In my case, being further away actually helped me appearslightly taller.
Rob further away than Jenny, but appearing a bit taller