How to read before and after photographs

Before and after photographs are the primary marketing material of the aesthetics industry and the weakest form of evidence in it. That is not because clinics are dishonourable. It is because a face photographed twice under different conditions will look different regardless of what happened in between, and the conditions that flatter a result are the same conditions any reasonable person would choose when taking a nice photograph.

You do not need to distrust the images. You need to know which parts of them carry information.

What a controlled pair looks like

Clinical photography follows a discipline. The camera sits at a fixed height and distance. The lighting is the same in both frames, ideally diffuse and from the same direction. The background is plain and identical. The subject holds the same expression, usually relaxed, with the head level and the chin neither lifted nor tucked. Hair is off the face. Makeup is either absent in both or present in neither. Jewellery is consistent.

When all of that is held constant, a difference in the image is a difference in the face. When any of it moves, the image can show a change that did not occur.

Lighting does most of the work

Lines and folds are shadows. Change the angle of the light and you change the shadows without touching the skin. Overhead light deepens the tear trough and the nasolabial fold. Light from the front and slightly above flattens both. A ring light fills every crease on the face and is the single most effective anti-ageing device in the industry, costing about thirty pounds.

Look at the catchlights in the eyes. If the reflected light source is a different shape, size or position between the two photographs, the lighting changed. Look also at the shadow under the nose and the jaw. Those two shadows tell you where the light was standing.

Angle, distance and the chin

Camera height changes a jawline more reliably than most treatments do. A camera slightly above eye level lengthens the neck, sharpens the jaw and reduces the appearance of submental fullness. A camera below eye level does the opposite. A tucked chin creates a fuller under-chin, a lifted chin removes it.

Distance matters too, because a shorter lens distance exaggerates whatever is nearest the camera, typically the nose and the central face. Two photographs taken at different distances are not comparable even if everything else is identical. Check the relationship between the ears, the shoulders and the edge of the frame.

Expression, and the dynamic problem

For botulinum toxin results this is decisive. A before photograph taken with the brow actively raised and an after photograph taken at rest will show a dramatic difference that has nothing to do with the injection. A fair pair shows both images at rest, and ideally a second pair with both images in maximum expression, for example frowning hard in each.

A smile changes the midface, the nasolabial fold and the eye area substantially. If one image smiles and the other does not, no comparison is possible. This is worth knowing before you assess filler results, where the difference between animation states is largest. We cover why in the anatomy of an ageing face.

The time interval, and what it hides

An after photograph taken at the right moment can flatter or mislead in both directions. Immediately after dermal filler, swelling adds volume that will not last, so a same-day image overstates the result. Botulinum toxin takes several days to begin working and around two weeks to reach full effect, so an image taken at day three understates it.

The interval should be stated. Two weeks is a reasonable point for toxin, four weeks for filler once swelling has settled, and longer for anything collagen mediated. What is far more useful, and far rarer, is a photograph at six months, because that is when you learn whether a result held. Ask for one.

Editing, filters and skin

Smoothing filters affect skin texture and are usually visible around the hairline, the eyebrows and the edges of the nostrils, where the algorithm blurs boundaries it cannot resolve. Look for lost pore detail, unnaturally even skin tone, and eyelashes that fade rather than end. Colour grading also matters: a warmer after image reads as healthier without anything having changed.

Then there is the ordinary makeup problem. Concealer under the eyes, a matte base, contour along the jaw and a defined lip line will produce a convincing result on their own. If the before photograph is bare and the after photograph is made up, the treatment has an unfair advantage.

Whose work are you looking at

The image should be the work of the practitioner who will treat you, taken in the clinic you will attend. Manufacturer supplied images, stock imagery and results from a training course led by somebody else are all in circulation. Asking who performed the treatment shown is entirely reasonable, as is asking whether the images are of this clinic's own patients.

Consent matters here too. Patient images should be published with specific consent, and a clinic that is careless about that is telling you something about its record keeping generally, a point our consultation guide returns to.

The questions that get you a real answer

• Are both images taken in the same room, with the same lighting and camera position?
• How long after treatment was the after image taken?
• What was used, in what quantity, and by whom?
• Do you have a result at six months on the same patient?
• May I see a case where you were not happy with the outcome and what you did about it?

That last question is the useful one. Every practitioner has had results that needed correcting. Somebody who can describe one calmly, and explain what they changed, is showing you their judgement, which is the thing a photograph cannot show. Pair it with the register checks in verifying credentials.