Lens protectors: cheap insurance for the glass, at a cost that only shows up after dark

A scratch on your display is annoying. A scratch on the ultra-wide lens is in every single photo taken from that moment on — usually as a soft veil across bright areas, or a smear of flare around light sources.

It is also awkward to fix. On most modern phones the rear camera glass is bonded into the housing, so replacement is a workshop job rather than a part you swap, and it costs a meaningful fraction of the phone’s value.

Against that, a lens protector is one of the cheapest accessories on the shelf. Where the environment is genuinely abrasive, the arithmetic is easy.

Every additional air-to-glass surface reflects a little light. In daylight this is invisible. Point the camera at a streetlight, a car headlight or a stage light and it becomes obvious: light bounces between the protector’s inner face and the lens, returning to the sensor as ghost images and haloes around bright points.

A cheap uncoated protector is markedly worse here than a properly anti-reflective coated one. If you photograph at night at all, that coating is the specification that matters, not the hardness claim.

There are two further failure modes worth knowing. If the protector covers the flash, its light reflects off the inner surface straight back into the lens and washes out the entire frame — a much more dramatic problem than flare. And any dust trapped between protector and lens stays there permanently, showing up in every shot; unlike a smudge on the front, you will not notice until you review the photos.

Most cases now include a raised lip around the camera module that holds the glass clear of whatever surface the phone is resting on. That solves the single most common wear scenario — phone laid face-up on a table or desk — without putting anything in the optical path.

If your case already has that lip, and you are not routinely around sand, grinding dust or loose grit, you probably do not need a lens protector at all. The case is doing the job.

Buy one if you work on sites or in workshops, spend time at beaches or in deserts, carry the phone loose in a bag with keys and coins, or hand it to children. In those settings the abrasion is real and constant.

Do not buy one if you shoot a lot at night or in low light and are unwilling to pay for a coated version, if your case already has a raised lip and your environment is ordinary, or if your phone has a sensor — LiDAR, laser autofocus — sharing the module that the protector would cover.

If you do buy, check the cutouts against your exact model before fitting. The layout differs between Pro and non-Pro variants of the same year, and a protector that covers a focus sensor causes problems that look like a broken camera.