Field guide
Guides: thermal imaging and night vision on a phone
Straight answers about thermal imaging, infrared and night vision — what a phone can really see, and what needs hardware.
Does the iPhone have a thermal camera?
No iPhone has ever had a thermal sensor, and the iPhone 17 does not either. Here is what the infrared hardware in your phone actually does.
What is thermal vision?
Thermal vision is seeing the infrared light objects emit because they are warm, rather than the visible light they reflect. It is not night vision.
Night vision vs thermal — which one do you actually need?
Night vision amplifies the light that is already there. Thermal imaging senses heat and needs no light at all. They fail in opposite conditions.
Infrared vs thermal camera: are they the same thing?
Every thermal camera is an infrared camera, but most things sold as infrared cameras see reflected near-infrared light, not heat. Here is how to tell them apart.
How does a thermal camera work?
Everything warmer than absolute zero glows in infrared. A thermal camera collects that glow, measures it with a microbolometer and paints it in colour.
Can I use my phone as a thermal camera?
Not on its own. Ordinary phones, iPhone included, have no thermal sensor: you need a plug-in camera or a rugged phone with one. Apps only copy the look.
Infrared camera apps, honestly
"Infrared" covers two completely different things, and app listings blur them constantly. Here is what an infrared camera app on an iPhone really does.
Does your phone have infrared?
The iPhone has infrared for Face ID, no emitter for controlling a TV, and no thermal sensor. Here is which infrared your phone has, and what you can reach.
Can a thermal camera see through walls?
A thermal camera sees the surface of a wall, never behind it. What looks like x-ray vision is heat reaching the surface — which is why it finds pipes.
Why is night vision green?
Night vision is green because of the phosphor screen inside an image intensifier tube — and because the eye pulls more detail out of green.
How much does a thermal camera cost?
Thermal cameras run from a phone attachment to a professional instrument, and the price is driven by one number — how many pixels the sensor has.
Do black light apps actually work?
A phone screen cannot emit ultraviolet, so no app turns your phone into a black light. Here is what the apps really do — and what a real UV torch costs.
What is night vision, and what does it actually look like?
Night vision amplifies the light already there and shows it on a phosphor screen. Here is what that looks like in practice — and why film gets it wrong.
How to choose a thermal camera
There is no single best thermal camera — there is the right resolution, lens and price for the job you have. Five questions that narrow it down.
How to film a convincing ghost-hunting clip
Found-footage horror has a visual grammar — grain, a bad frame rate, a handheld wobble, almost no light. Here is how to get it on a phone.
How do night vision goggles work?
Night vision goggles amplify the little light there is, using a photocathode, a microchannel plate and a phosphor screen. Thermal imaging is different.
How much do night vision goggles cost?
Night vision runs from under $100 for a digital monocular to well over $8,000 for Gen 3 goggles. The tube inside sets the price; here is what each band buys.
Finding draughts, damp and missing insulation with thermal imaging
Thermal imaging is the one job where nothing else comes close — but only in the right conditions. When to survey, and what each pattern really means.
Renting a thermal camera instead of buying one
Most people need a thermal camera for one afternoon, not for a lifetime. Where to hire one, what to check, and how to make the single day count.
The twenty looks, explained
Eight thermal palettes, five night treatments and seven FX looks — what each one is imitating, where it came from, and which scenes it actually suits.
Thermal camera apps for iPhone, compared
iPhone thermal camera apps fall into two groups — companion apps for a clip-on sensor, and live camera effects. Knowing which you are downloading helps.