Every card passes through CALIBER in roughly sixty seconds. In that time, over one hundred physical measurements are captured and analysed. Here's what each one does.
The principle
Every physical object has measurable properties. A trading card is no exception. Its thickness, weight, surface texture, material composition, and response to different wavelengths of light are all measurable quantities. Take enough of these measurements with enough precision, and you can describe the card completely — its authenticity, its condition, its history.
CALIBER's grading approach is built around this idea. Rather than looking at a card and forming a judgement about it, CALIBER measures the card and reports the results. The grade emerges from the data, not from interpretation. The same measurements also create a card fingerprint — a physical signature that can be matched on future submissions to confirm the card's identity over time.
Transmitted light — the black core test
Genuine Pokémon cards, Magic cards, sports cards and most trading cards are manufactured with a thin black core layer sandwiched between the front and back printing. In genuine stock this is carbon-black paper — paper manufactured with carbon black pigment integrated into the pulp, not printed on the surface. Carbon black is an extremely efficient absorber across visible light and into UV and IR, which is why a genuine card is genuinely opaque under transmitted light.
CALIBER automates this test with precision. A calibrated LED panel below the card shines uniform white light upward through the card. A high-resolution camera above captures the transmitted light pattern. Genuine cards appear as solid black shapes. Fakes glow visibly.
Counterfeit cards are typically printed on standard white or off-white stock with a black layer printed on the surface rather than integrated into the paper. Surface printing does not achieve the same opacity: light leaks through.
The same pass also enables card fingerprinting. The carbon-black fibres inside the core are randomly distributed during manufacture. That distribution is effectively unique per card — like a snowflake — and it does not change when the face of the card is scratched, cleaned, or cosmetically repaired. That is why a fingerprint can still match the same physical card even if the visible surface changes.
Photometric stereo — surface reconstruction
If you photograph a card under flat overhead lighting, the result is a picture of the card's artwork and text. If you photograph the same card under light coming from one side, the shadows cast by every tiny scratch, dent, and print defect become visible.
Photometric stereo takes this principle further. CALIBER photographs each card four times, with light coming from four different directions — left, right, front, and back. By comparing how the shadows change between these four images, an algorithm reconstructs the actual three-dimensional surface of the card at microscopic scale.
The output is not a photograph but a depth map. Every scratch is measured by its depth and length. Every dent by its volume. Every print defect by its extent. At CALIBER's imaging resolution of eighty pixels per millimetre, surface features as small as a tenth of a millimetre are captured precisely.
Structured light — 3D shape measurement
Cards are supposed to be flat. In reality, they warp. Heat, humidity, storage conditions and manufacturing variation all cause cards to develop subtle bows or twists. A bowed card is graded lower than a flat one, and structured light is the measurement that detects this.
A digital light projector casts a series of precisely known stripe patterns onto the card. A camera records how those stripes bend as they hit the card's surface. The mathematics of how a known projected pattern distorts when it lands on a curved surface allows the card's three-dimensional shape to be reconstructed with sub-millimetre precision.
The result is a contour map of the card. Perfectly flat cards produce flat maps. Bowed cards produce curved maps. The precise shape and magnitude of any warp is quantified and included in the grade.
Ultraviolet fluorescence — invisible signatures
Most people have seen the effect of UV light in clubs and at airports. Certain materials — banknote security features, white shirts, bank security strips — glow under UV light because they contain chemicals that absorb ultraviolet wavelengths and re-emit them as visible light. This is called fluorescence.
Modern trading cards contain security features that behave the same way. Printing inks have specific fluorescence responses. Coatings and varnishes fluoresce distinctively. Holographic elements contain signatures only visible under UV. CALIBER captures two independent UV images of every card — one at 365nm (deep ultraviolet) and one at 395nm (near ultraviolet) — because different security features respond to different wavelengths.
A genuine card produces a specific, predictable UV signature. A counterfeit card produces a different signature, regardless of how convincing its visible appearance might be. The UV passes are one of CALIBER's strongest authentication tools.
Infrared transmission — seeing beneath the surface
Infrared light has a longer wavelength than visible light. This means it penetrates thin layers of material that are opaque to our eyes. CALIBER uses 850nm infrared illumination to see through the top layer of printing and inspect the structure of the card underneath.
This is how CALIBER detects layer substitution, hidden tampering, and damage that has been cosmetically repaired. A card that has been re-backed — where the back has been replaced to hide damage — looks perfect to the eye but reveals its history under infrared.
Blue light — coating and surface treatment
Blue light at 450nm wavelength sits at the edge of the visible spectrum and reveals surface features that are hard to see under normal lighting. This includes adhesive residue from sleeve damage, coating inconsistencies, trimmed edges that have been disguised, and surface treatments applied post-manufacture.
Weight — material consistency
Every genuine card of a given type weighs a specific amount. A standard Pokémon card weighs between 1.7 and 1.8 grams. Deviations from this range indicate one of several possibilities: counterfeit card stock (usually lighter or heavier), moisture damage (heavier), or thickness variation (potentially either).
CALIBER weighs every card to sub-gram precision. This alone is not a grading factor, but combined with the other measurements it provides an important confirmation signal.
Putting it all together
The sixty-second measurement process captures all of the above in sequence: transmitted light for the authentication test, then weight, then the full spectral sequence of UV, IR and blue, then photometric stereo from four angles, then structured light for shape analysis — first on the front face of the card, then after it is flipped, again on the back face.
Thirty-three measurements in total. From those measurements, the grade is calculated deterministically — the same inputs always produce the same output. No interpretation. No judgement. No opinion.