Have you ever seen a photo where an otherwise plain shirt suddenly shimmers with colorful, wavy patterns that aren't actually there? This is called the moiré effect – a visual interference pattern that occurs when two fine, regular grids overlap. In photography, this mainly affects clothing with fine patterns meeting the pixel grid of the camera sensor.
The physical explanation: interference between two grids
A camera sensor doesn't capture an image continuously – it samples it using a fixed grid of millions of pixels. When this sampling grid encounters a subject with a similarly fine, regular structure – such as pinstripes or a tight herringbone pattern – so-called aliasing interference occurs: the two grids overlap, creating a third, new pattern that is larger and coarser than either original pattern and doesn't actually exist in reality. Typical results are wavy, often rainbow-colored stripes that shift as soon as the camera or subject moves slightly. The finer the fabric pattern relative to the sensor's resolution, the stronger the effect. Cameras without an optical low-pass (anti-aliasing) filter, which many modern models now omit for higher sharpness, tend to show it even more strongly.
Why this matters for your shoot
For a business or application photo, many people like to wear a striped shirt, a pinstripe suit, or a jacket with a fine check or herringbone pattern. But exactly these fabrics are the classic triggers for moiré. The tricky part: the effect is invisible when trying on the outfit in front of a mirror and only shows up in the finished photo – often only on screen at full resolution. Unlike an exposure error, moiré can only be removed afterward to a very limited extent, and only with visible loss of quality, because the interference pattern is inseparably woven into the actual image detail. In some cases, the only solution is a new photo in different clothing.
Not just clothing: screens are affected too
The same effect occurs whenever two pixel grids overlap – for example, when a camera films or photographs a screen, such as during a video call or when someone photographs a display instead of using the original file. Here too, the screen's pixel grid and the camera sensor's pixel grid overlap and produce the same wavy patterns. That's why images photographed off a screen often look slightly flickery or striped, even when the original image was flawless.
Our tip: plain and coarsely structured is safest
The most reliable solution is to prevent the problem from occurring in the first place: plain-colored or coarsely structured clothing without fine stripes, checks or herringbone patterns reliably avoids moiré – which matches our advice in the application photo article that plain-colored tops almost always work best. If you're unsure about a piece of clothing, just bring it along to your appointment – we'll take a look beforehand and advise you on whether it works for the photo or whether an alternative would be a better choice.