Colour consistency
Colour consistency: the problem
VeriVide products and technologies provide solutions to a naturally occurring problem. Namely, that a colour or shade looks different when viewed in different light conditions.
The difference may be extreme and obvious. For example, a car that is bright red in daylight may appear brown under sodium street lighting. But in supply chains, even minor differences in perceived colour can be problematic.
Colour accuracy is a major concern for manufacturers asked to supply products in very precise shades. Colour checking in natural daylight won’t work because there is no such thing as uniform daylight. It differs according to time of day, season, location, climate, weather and atmospheric conditions.
As a result, colours that look right when manufactured may look wrong when delivered. And if disputes then arise, how are they to be resolved?
It’s worth noting that colour perception varies from human to human, and we can each recognise several million colours. Unsurprisingly, it can be difficult to get even two people to agree that a particular shade is 'right' or 'wrong'.
The VeriVide solutions
The VeriVide solution is a range of products based on:
- Standardised artificial light sources
VeriVide lamps mimic daylight to international standard D65, or to other standards specified by major retailers.
If everyone in a supply chain uses the same agreed VeriVide light source, variations in natural light become irrelevant. Colour can be viewed and measured in exactly the same lighting conditions at every stage of design and product development. VeriVide's Colour Assessment Cabinet LED P.O.S. ensures colour consistency under LED in-store lighting to eliminate colour communication problems for brands and retailers.
- Digital colour assessment
VeriVide’s DigiEye is the first camera-based system to make the transformative leap from human (subjective) to automated (objective) colour measurement. DigiEye assesses colour rapidly, accurately, impartially, economically – and globally when supply chain partners all use DigiEye to share data.
The potential of DigiEye is recognised increasingly in sectors with no strong tradition of colour assessment. For example food and pharmaceuticals, where DigiEye can convert colour and appearance data into reliable information about product quality.
Understanding colour and light sources
In industry, colour assessment plays a growing role in quality assurance. To get reliable results that everyone can agree on, three essential requirements are:
- A high-quality light source.
- Standardised viewing conditions.
- A means of capturing objective data.
Let’s look at each of these in more detail.
Light sources
VeriVide lamps take care of all the science but for the record, finding the right light source for a given application depends on three factors:
- Colour temperature
This has nothing to do with heat. It describes the appearance of the light a lamp emits. The lower the colour temperature, the ‘warmer’ (redder) the light; the higher the temperature, the ‘colder’ (bluer) the light.
- Colour rendering index (CRI)
An index from 0-100 measures how faithfully colours are rendered by a lamp compared to a reference light source. Low values indicate poor colour rendering, while 100 is an exact match.
- Spectral power distribution (SPD)
Different light sources emphasise different parts of the colour spectrum, affecting how the eye sees colour. SPD rating classifies each light source. VeriVide’s D65 lamp is internationally recommended for colour assessment, as it emits the whole colour spectrum almost equally.
Standardised viewing conditions
Everyone in a supply chain needs to ensure that their viewing equipment and environment meets internationally agreed standards.
Best practice is to use VeriVide Colour Assessment Cabinets. These ensure an identical viewing environment throughout the supply chain.
Colour assessment cabinets must have neutral and blemish-free matt grey interiors and a high quality, distortion-free lamp reflector.
The siting of the cabinet is also critical. All external sources of interference should be removed. For example, nearby windows should be fitted with grey blinds and nearby general lighting should be VeriVide 200-300 lux Artificial Daylight.
It is good practice to offer colour perception testing to personnel involved in making colour decisions.
It is also advisable to consider at design stage the desired appearance of products at point of sale or in everyday use, as most products will ultimately be seen and judged in environments outside the supply chain.
Capturing objective data
Colour assessment has traditionally relied on human vision. A weakness of this practice is that even in standardised viewing conditions, and even when assessors are highly experienced, different individuals may still see the same colour differently.
Nor is it possible to record objectively what the human eye sees. Some judgments must of necessity be subjective, making communication of reliable colour data problematic.
VeriVide’s DigiEye system is the innovation that transforms everything. DigiEye is a camera-based system that digitises and stores data in a form that is totally objective and authoritative.
DigiEye’s other advantages - speed, versatility, economy - give it unlimited potential for much wider industrial applications. Colour data can now be used cost effectively to measure non-colour characteristics such as product freshness and ingredient distribution.
Digitised data can also, of course, be communicated globally and shared by other DigiEye systems in the same supply chain or enterprise network.
