Skip to content
Dyed film blocks light but very little heat and fades to purple. Metallised film rejects heat well but interferes with radio signals. Carbon film is stable and metal-free with solid performance. Ceramic film rejects the most infrared heat with no signal interference and no colour shift, which is why it costs the most and lasts the longest.
On the glass, all four look broadly alike. A dark window is a dark window. The difference is entirely in what the film is made of, and it shows up in three places: how hot your car gets, what colour the windows are in four years, and whether your phone works properly inside the cabin.
Darkness and heat rejection are not the same property. This is the single most useful thing to understand before you spend money. A very dark dyed film can reject less heat than a nearly clear ceramic one.
The four film types
Dyed film
The oldest and cheapest technology. A layer of dye is sandwiched between an adhesive layer and a protective top coat. The dye absorbs visible light, which is what makes the window look dark.
Absorbing light is not the same as rejecting heat. The energy is absorbed into the film and the glass, and a good portion of it radiates into the cabin anyway. Dyed film gives you privacy and glare reduction, and comparatively little else.
Its real problem is longevity. Ultraviolet light breaks the dye down. In Southern California sun that process is quick, and it does not fail gracefully — the neutral grey shifts toward purple, and the adhesive starts to give up, producing the bubbling everyone recognises.
Choose it if: you are selling the car soon, or you need the lowest possible price and accept it is temporary.
Metallised film
Microscopic metallic particles are embedded in the film. Metal reflects infrared radiation genuinely well, so heat rejection is a real step up from dyed, and the film is durable — it does not fade the way dye does.
The problem is what else metal does. A conductive layer across your glass can attenuate radio frequency signals passing through it: cellular data, GPS, satellite radio, tyre pressure sensors, keyless entry.
On a 2005 car with an aerial on the roof, this barely mattered. On a modern vehicle with antennas embedded in the glass and phone-as-key functionality, it matters a great deal. Metallised film also has a slightly reflective, shiny appearance that some drivers dislike, and California regulates reflectivity separately from darkness.
Choose it if: rarely, on a modern car.
Carbon film
Carbon particles replace the metal. Carbon is not conductive, so the signal problem disappears entirely, and it does not fade the way dye does — the colour is stable because carbon is stable.
Heat rejection is good, sitting comfortably between metallised and ceramic. The finish is a flat, matte black without the mirror-like quality of metallised film, which most people prefer aesthetically.
Carbon is the sensible middle of the market: markedly better than dyed, meaningfully cheaper than ceramic, with no significant drawbacks beyond not being the best.
Choose it if: you want durable, good-looking film without paying top rate, and cabin temperature is a preference rather than a priority.
Ceramic film
Non-conductive ceramic nanoparticles do the work. Ceramic has an unusual property: it can be tuned to block infrared wavelengths while still passing visible light. That decoupling is the whole point.
It means a ceramic film can be relatively light — letting you see out clearly, and staying within California’s front window limit — while still rejecting a large share of the infrared energy that actually heats your car.
No metal means no signal interference. No dye means no colour shift. Optical clarity is the best of the four, which matters at night when a cheap film scatters oncoming headlights into haze.
Choose it if: you are keeping the car, you park outdoors in Los Angeles, or you drive an electric vehicle.
Side by side
| Dyed | Metallised | Carbon | Ceramic | |
|---|---|---|---|---|
| Heat rejection | Low | Good | Good | Best |
| UV blocking | Moderate | High | High | Highest |
| Colour stability | Fades to purple | Stable | Stable | Stable |
| Signal interference | None | Yes | None | None |
| Optical clarity | Fair | Fair | Good | Excellent |
| Reflectivity | Low | Noticeable | Low | Low |
| Typical lifespan | 2 – 5 years | 5 – 10 years | 7 – 10 years | 10+ years |
| Relative cost | $ | $$ | $$ | $$$ |
The numbers that matter on a spec sheet
Film manufacturers publish several figures. Three are worth understanding.
VLT (Visible Light Transmission) is the percentage of visible light passing through. This is the number California regulates and the one that determines how dark the window looks. It says nothing about heat.
IRR (Infrared Rejection) is the percentage of infrared energy blocked. Treat headline IRR figures with some caution — they are sometimes quoted at a single favourable wavelength rather than across the full infrared band, which produces impressive but not very meaningful numbers.
TSER (Total Solar Energy Rejected) is the most honest single figure. It accounts for ultraviolet, visible and infrared energy together, which is what actually heats your cabin. If you compare films on one number, compare TSER.
A film advertising 98% infrared rejection alongside a TSER of 45% is telling you two things, and only one of them is useful.
What this means for your interior
Ultraviolet light is what fades and cracks a cabin. Dashboards go brittle, leather bleaches and stiffens, trim discolours. Ordinary automotive side glass blocks a portion of UVA but not all of it, which is why one side of a long-owned car often shows more wear than the other.
All quality films — carbon and ceramic certainly, metallised generally — block essentially all ultraviolet light. This is one area where the mid-tier options are not meaningfully behind the premium ones. Where they diverge is heat, not UV.
Why this matters more in Los Angeles
Two local factors change the calculation.
The first is simple sun exposure. Los Angeles gets a great deal of clear-sky sunshine, and a lot of parking is outdoors. Film that degrades under ultraviolet degrades faster here than in Seattle.
The second is California’s front window rule. Because Vehicle Code 26708 restricts front side windows to above 70% combined transmission, you cannot use darkness to reduce heat on the front doors. The only lever available is film technology — which is precisely what ceramic is good at. It is the one film that can be light enough to be legal at the front and still do real work. Our guide to window tinting in Los Angeles covers the practical side of that constraint.
Frequently asked questions
What is the main difference between ceramic and carbon window tint?
Both are metal-free and colour-stable, so neither interferes with signals or turns purple. Ceramic rejects substantially more infrared heat and has better optical clarity. Carbon delivers most of the durability benefit at a lower price.
Does darker tint block more heat?
Not reliably. Darkness measures visible light, heat rejection measures infrared. A light ceramic film routinely outperforms a much darker dyed film on heat, because the two properties are controlled by different mechanisms.
Why does cheap window tint turn purple?
Dyed film relies on a dye layer that ultraviolet light breaks down. As the dye degrades, the neutral grey pigment fails before the others and the window shifts toward purple. Carbon and ceramic films contain no dye, so they cannot fail this way.
What is TSER and why does it matter more than IRR?
Total Solar Energy Rejected accounts for ultraviolet, visible and infrared energy together, which is what actually heats a cabin. Infrared rejection figures are sometimes quoted at a single favourable wavelength, producing a headline number that overstates real performance.
Will metallised tint really affect my phone signal?
It can. The metal layer that rejects heat also attenuates radio frequency signals crossing the glass. On modern vehicles with glass-embedded antennas and phone-as-key systems, the effect ranges from marginal to genuinely disruptive.
How long does each type of film last?
Dyed film commonly gives two to five years before visible failure. Metallised and carbon typically run five to ten. Quality ceramic film regularly exceeds ten years and is often sold with a lifetime warranty against bubbling, peeling and colour change.
Is ceramic tint worth double the price of carbon?
If you are keeping the car for years, park outdoors, or drive an electric vehicle, yes. If you are selling within a year or the car lives in a garage, carbon is a rational choice and you will not feel short-changed.
Can I mix film types on the same car?
Technically yes, and some people fit a light ceramic on the front to stay legal with a darker carbon at the rear. Be aware the two will not match exactly in tone, which is visible from outside at certain angles.
Does window film block all UV rays?
Quality carbon, metallised and ceramic films block essentially all ultraviolet light. Basic dyed film blocks considerably less. UV blocking is the one area where mid-tier films are close to premium ones.
Does ceramic tint look different from carbon?
At the same VLT they look similar from outside. From inside, ceramic is noticeably clearer, particularly at night, because it scatters less light. Cheaper films produce a haze around oncoming headlights that ceramic largely avoids.
Choosing for your car
If you want a straight recommendation: carbon if the car is a short-term keeper, ceramic if it is not. For anything electric, ceramic, for the signal reasons above.
We stock and fit across the range and will tell you honestly when the upgrade is not worth it for your situation. Request a quote with your vehicle details, or read more about ceramic window tinting and our wider range of services.