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"That UFO in Your Photo Is Probably Your Lens: Camera Artefacts Explained"
"Round orbs, hexagons and ghostly shapes in night photos are usually made by the camera, not the sky. Here is how each artefact forms and how to check your shot before you report it."
By Track the Unknown ·
The question behind almost every blurry night photo we receive is the same: there was nothing there when I took the picture, so what is the glowing shape in my frame? Nine times out of ten the answer is the camera, not the sky. Here is how the common artefacts form, why they seem to cluster in autumn and winter, and how to check your own shot.
Out-of-focus lights become discs and hexagons
A lens that fails to focus a point of light does not render a point — it renders the shape of its own aperture. Out-of-focus streetlights, car headlights and aircraft lights turn into soft discs or polygons, with the number of sides set by the aperture blades. Phone cameras do this too when autofocus locks onto empty sky instead of the light itself. The result is a round or hexagonal "orb" with crisp edges that looks far more solid than the light ever was.
Dust, flash and the indoor orb
When a flash fires close to the lens, dust motes and tiny insects a few centimetres away are lit out of focus and appear as pale, semi-transparent discs drifting across the frame. Photographers call them orbs. They are absent from what you saw with your eyes because your eyes do not have a flash firing centimetres from the pupil.
Lens flare, ghosts and internal reflections
A bright source — the Moon, a streetlight, the Sun just below the horizon — bounces between the elements inside a lens and lands as ghosts: a chain of faint shapes running through the centre of the frame, usually opposite the source. Coloured rings, hexagonal patches and a milky haze across the image are all forms of flare. Flare tells you a bright light was in or just outside the frame. It does not tell you what you were looking at.
Sensor dust and night-mode smears
On an interchangeable-lens camera, dust on the sensor leaves small dark spots that sit in the same place in every frame. Take two photos and compare: if a mark does not move between shots, it is on the camera, not in the sky. Phone night mode stacks several exposures over a second or more, so anything that moves during the shot — a plane, a satellite, your own unsteady hands — can come out as a smear, a dotted line or a doubled shape.
Rolling shutter and drone lights
Phone sensors read the image line by line rather than all at once. Fast, bright lights — drone strobes, rotating beacons, even the flashing lights on a distant aircraft — can come out sliced into bands, tilted or repeated. If a quadcopter's lights look bent or stretched, you are probably seeing the sensor's read-out speed rather than an impossible manoeuvre.
Why "orb" photos spike in autumn and winter
Reports of round glowing objects climb when the sun sits low, nights draw in and more photos are taken in dim light. Low sun angles send light bouncing through the elements inside a lens. Cold, dark evenings put dust, insects and condensation in the path of torches, headlights and flash. And people photograph the sky after dusk more often. There is no evidence the sky itself changes with the season — the camera conditions do.
Banding, compression and screen grabs
Low light, digital zoom and messaging-app re-compression all conspire against a night video. Blocky bands around a bright light, purple fringing and a dotted trail across the frame are usually compression rather than structure. A screen grab of an already-compressed video is compressed twice, so the detail you zoom in on may have been created by the act of zooming rather than by the object. Always keep — and send — the original file.
How to check your own photo
- Clean the lens with a microfibre cloth; a fingerprint smears everything.
- Retake the shot with flash off, and tap to focus on the light itself.
- Compare with what you saw at the time — most artefacts never reproduce in person.
- Note the time, direction and whether the object stayed in the same place across frames.
- Run it through the free sky checker before you assume it is something new.
If the object moved between frames while the camera was still, was silent, and matches a satellite pass or a meteor, you have your answer. If it does not, it is worth a look in the common explanations — and worth reporting if it still does not fit.
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Tags: camera artefacts, photo analysis, bokeh, lens flare, dust orbs, night photography, orbs, rolling shutter, identification, reporting