Safety in Colour

Ten days (And nights) deep in the Botswana Bush heightens the senses as the battle for survival shifts to more fundamental issues like eat or be eaten. Its times like this that highlight the advantages man has over animals biologically, one of the most important being the ability to see in colour. Both animals and man respond well to movement, but mans ability to also finely discern one colour from another offers a distinct advantage.

Humans are able to see very fine shades of green from drab olives to pale lime. This helps us spot a predator in the day with ease, but helps less in the dark especially if there is no moon. While camouflage breaks up the human shape, colour discernment is a key factor in our survival outdoors, to such an extent that our sense of smell is demoted to a back up third sense after hearing. 

Still in the bush, its not wise to wear bright white, especially those nicely optically brightened garments that look cool at a trendy night spot, but wave a challenge in the face of predators, or at very least scare of the more timid types. At the other extreme, I have experienced that downside of driving a black car. During the day in Kruger Park, while slowly coasting along looking for game, a large bird all but flew into the windscreen. Apart from it being an extra 10-15 degrees hotter in the car (Without aircon) I put it down to a bird brain mentality. It was only when shortly afterwards that a large bull elephant nearly walked "Through" our car did I realise the basics of colour physics in action. The Bull may have sensed our movement, but as we were all black, he basically "Saw:" a hole or shadow in the road ahead, and continued boldly on. Mutual surprise, followed by mutual trumpeting in and outside the car, and thankfully zippy acceleration, got us out of a hot spot.

Rescue workers on the other hand will always tell you to wave something white, yellow or bright red to be noticed at sea, in the bush, on a mountain or anywhere else in the wild. There are many tales that a chance glimpse of a colour out of the ordinary helped to save a lost person.

We now see a proliferation of Hazard and Safety gear from stripes on your Nikes to Yellow jackets worn by Police. Even the ragged car guard seems to grow some authority when wearing a Haz jacket.

Next time you are choosing a Fashion Colour, think where you may end up wearing it, and decide if it will be good to be seen, or ghide!

The Power of Training

Nearly all of our support requests from customers have been covered in the initial installation and implementation training. Like sport, the phrase "Use it or lose it" also applies and I have a lot of sympathy for lab staff who are moved around from task to task without having time to either bed down their own knowledge, or share it with other colleagues.

Surveys show that in Southern Africa, and probably for the North as well, managers complain most about having unskilled staff. At the same time, there seems to be a "Grudge Purchase" attitude towards purchasing adequate training.

Things move too fast and change too often expect technical staff to just be able to pick up new software, instruments and technologies as they go along. In any case, sufficient time is never available for learning.

We make it a point in our business to trace users regularly and see if our installed systems are still up and running, and all too often we have to implement a rescue plan.

Apart from typical user skills not being taught in the first place, IT plays a fairly disruptive role in the smooth operation of systems. Firstly, there is the dreaded upgrade. Whenever software and hardware changes are made, we can be sure that system First Aid will be required. Often these upgrades are carried out without any consultation regarding their implications or impact on Laboratory Staff productivity.

Secondly, the rapid staff turnover or change. Often, a key person trained on site leaves shortly afterwards, and even if its temporary like Maternity Leave, it is usually 100% Disruptive.

Laboratory mergers, moves to new sites and simple cuts are also responsible for extremely stressed conditions. Another danger area is senior managers who insist on being trained, but who never actually put hands on the equipment later. They seldom have or take the time to pass down the required knowledge to ensure their whole user team is capable of carrying out the required tasks.

Another huge issue is time. To schedule a training visit takes more time than the training itself.

So what to do?

1. Take training offers whether free or reasonably priced as often as possible.
2. Budget training time as well as funds
3. Appoint a responsible person to deliver a result, not man a station
4. Allow Laboratory Staff a decent internet connection. The IT guys can monitor it for abuse, but don't limit the user too much, they must be free to look up terms and definitions, or joining supplier websites for Webinars.
5. Why not actually encourage reading a manual? These days they are very well written and usually cover all the FAQ's. When supplied in PDF form, they are also word searchable, which also saves time.

Before you over promote and over task a technical staff member, count the cost of their inability to actually manage the tasks that you have specified.

We invite you to take part in our training options, webinars etc.

What is the value of colour measurement?

Accurate colour measurement, or any light based test for that matter, is a lot cheaper than many traditional testing methods, particularly as its non destructive. It is however not free. So when is colour measurement essential?

Lets take a typical Industrial Example - Auto manufacturing - Quality

Car makers tend to have very high standards, obtain parts from many different suppliers around the world, made of multiple materials with varying functionality. It is not possible to start matching doors to bodies, bumpers to bonnets and other accessories like plastic wheel trims and petrol caps on the assembly line. One of the many technical specifications include a colour specification. To be accurate and universal, the specification include about 14 rules to ensure that the different parts match well under various conditions. The cost of using Spectrophotometers far outways reprocessing of cars on the assembly line, as well as the possibility of a reduced quality perception by customers. The same approach also applies to the colour of the tail lights, the intensity of the headlamps and dashboard icon clarity. 

Example - Fashion Plastics - Branding and Formulation

Fast Moving Consumer Goods (FMCG's) run to very tight time constraints. Lets say a well known brand name is going to launch a new skin care product for a high selling season like Christmas. It can take plastic container manufacturers months to get the packaging approved working visually with physical samples.

Today, a designer can post a master colour on line, and by using a Spectrophotometer with Colour Prediction Software actually formulate the plastic colour within days. Packaging, either paper or plastic, can be married to all the related media according to master colour details. This results in lots of savings as well.

Example - Textiles - Matching Fabrics - Quality

Fashion is created at high speed and the market reacts very rapidly as well. While some garments might be OK with it, mostly we would like the left sleeve or leg to match the right sleeve or leg, even when these come from different rolls of fabric, maybe over months of delivery. Spectrophotometric's make this easy, speeding up fashion and eliminating defects.

Ask us about your application

What is Colour Difference Measurement

What are we actually doing when we measure colour? To understand this, we need to understand what our actual objective is:

• Compare one colour to another
• Obtain actual colour data 
• Predict a colour formulation
  
  This post will deal with the first task only.

Compare one colour to another

Colour Comparison is usually the first and simplest task to carry out.

There are many reasons WHY we want to compare colours, like batch to batch colour continuity, quality control or to ensure one part of an assembly matches another, say in the auto industry. Colour Comparison can also be useful for Color Grading like with Flour, Fruits and Fruit Juices etc.

We have done this visually since the first time colour continuity was important. Perhaps an ancient potter or carpet weaver saw this need.

As soon as we compare colour visually, we run into a number of problems. The first is, do two people agree on the comparison, due to possible colour perception defects in one or the other observer. The next problem is, the colour seems to change at different times of day, in different physical settings. Following from this, are two observers able to agree (An opinion) on a colour. Often a supplier and a customer have different expectations which "Colour" their opinions. (Seeing red as the saying goes!)

It soon becomes clear that we need a stable reliable device that can "See" colours like humans do, and relate the data without any judgement or opinion. Enter the Spectrophotometer or Chroma meter (Colorimeter).

Studies into HOW we perceive colour reveal that the perception (In the brain) is influenced by a number of factors:

• Illuminant Source (natural, artificial)
• Size of object
• Angle of observation
• Amount of data observed
• Proximity of the object to other objects of other colours

There are about 14 "Contextual" influences on colour perception comparison, which will be dealt with in more detail in future posts, but the conclusion is that the perception of colour varies, and can not be said to be a property of an object like say weight or dimensions, but are subject to the Contextual Conditions" under which the observation was made.

To this end, the CIE (International Commission on Illumination) an international body regulating standards, prescribe the various contextual specifications in detail.

In this post, let us assume that we are comparing two colours using one CIE certificated Spectrophotometer with a known setup and using a known CIE approved Colour Space Equation (Say L*a*b)

• Prepare an object for measurement
• Measure the object
• The instrument will return L*a*b values.

These values are almost meaningless to the observer, as it is very difficult to envisage what could has been measured from the values returned. In many cases however, Quality Assurance people who are number fixated WILL look at this number, and then compare it to a "Correct" number on record. IF (Huge IF) the values were obtained UNDER THE SAME CONTEXTUAL CONDITIONS, you may infer that the numbers are close or far, but what does the difference between one number and another visually mean? If you think you will get the same numbers measurement to measurement, its a fantasy. Thats not how this works.

The quick solution to Number Madness is to use a "Target" and "Sample" approach.

A Target will be the master colour you wish to achieve, and the Sample colour will be the current batch etc.

If you measure BOTH the Target (Known wanted colour) and the Sample at the same time under the same contextual settings, you can then expect to have some sane method of comparison. The CIE L*a*b standard also come with a Colour Difference equation known as Delta ( ∆ ) L*a*b.

If you set the Instrument or software to give a Colour Difference reading, you can then see what the implication of the differences may be.

So L =  Darkness (Black = 0) or Whiteness (White = 100)

   *a  =  Redness in the + side or Greenness in the - side. The numbers indicate the INTENSITY of redness    
            or greenness.

   *b =   Yellowness on the + side and Blueness on the - side, and the numbers the intensity as for *a

By comparing the DIFFERENCE between a Target and Sample, and by reducing the difference to an AVERAGE of the difference of Target to Sample you will end up with a single value say ∆ 1.5 . This is now a meaningful number. For instance a difference of 3 is clearly visible to the human eye, and 0.5 is hard to tell.

Future Posts will cover more detail, and you can looke now at the advanced information here

Colour Measurement and Eskom "Load Shedding"

South Africans will know that Load Shedding is our local quaint name for planned unplanned power failures. How does this effect you?

If you are a user of our Konica Minolta CM3600d or A Series Bench Tops or the Konica Minolta CM-5 Bench top spectrophotometers, how does this affect you?

Typically, if a PC and software is involved, surge protection and a UPS system will be required in any case. The CM-5 range however can work as stand alone models using their own firmware, but again as they are mains powered, a UPS system is recommended. This is more to protect the instrument from power surges than anything else, as UPS system are expensive and their useable working time is often quite short.

As it seems that the power issue is here for quite some time, we have another option: Both Bench Top Instrument types have portable hand held versions as well, which run on batteries. Contrary to what some may believe, the quality of these portables are of the highest standard, with specifications similar to that of their bench top versions. You can confirm both the CM3600d and CM-5 portable version specifications by comparing the catalogues of both versions.

The number of estimated measurements on battery is quite good, well enough for the two hour load shedding periods. An AC mains adaptor is also available for the portables should you wish to save a bit on battery life during normal power supply hours.

We have a number of customers who happily mix Bench Top and Portable in the same circle of application, and you have the added benefit of Field (At the customer) measurements as well.

Meat and Colour. Is Red the only Game in Town?

A lot has been said and written about the artificial colouring of meat either by some chemical treatment or trick lighting at the point of sale. While certain colourant's can be measured and tracked by their colour characteristics, and even light sources screened for "Unfair" or  "Flattering" lighting (Imagine if Hollywood was not allowed to cheat!) there are many more things Spectroscopy can do to evaluate or categorise output from your local butcher.

It has long been known that the composition of animal feeds can affect the colour of meat, which in turn can have a relationship with fat content, the type of fat content, and eventually health and even flavour outcomes.


Dr Cobus Ferreira completed a study in 2014 which demonstrates these assumptions, particularly with relation to Pork meat. it was found that Pork quality can be improved upon when using a natural feed additive CLA (Conjugated linoleic acid).

Details of the study cane be found here.Study details

You will notice that colour measurements were carried out with our Konica Minolta Chroma Meter CR400.

This instrument is one of the most used colour measurement devices in food research, partly due to its accuracy, reliability and affordability. Backward compatibility for 20 years also makes this model a very valuable research tool.




 

Colour Grading of Grain Flour - Wheat

A number of professions claim old age in their pedigree, but few have a better claim than Wheat Millers. Since farming crops became one of the first global addictions, bread flours have been milled to create flavour, texture, quality and ascetic appearance.

While today a minute portion of the crop is milled by Artisan Bakers, the vast majority globally is milled by large industrial groups using similar processes and equipment.

Like Fish, Bread whiteness increases the value of flour based baked products, but there is an industrial equation of time versus whiteness which has to be balanced. Added to this, over milling reduces the food value of flour.

In the 1950's scientists began to use Spectroscopy to try and standardise flour grades. The theory was good, but in practice, instruments were unreliable, the measurement fiddly and inter-instrument agreement near impossible.

This gave birth to the so called "Ring Test" where batches from various sources could be correlated to a "Known" standard (Actually and arbitrarily selected standard) and the various batch readings "Adjusted" (Corrected) accordingly. Never satisfactory, this type of procedure lasts up to the present day, although proper colour measurements have been carried out for decades by some Millers in some countries.

Some years back, South African Millers were fined for "Collusion" and while the merits of this is for another discussion, company's became weary of all using the same technology. This became the perfect time to introduce STANDARDISED rather than same systems to confirm with managements desire to be seen to be working above board.

Simply put, if millers could all use Kg to designate the weight of the packaging, the CIE L*a*b colour space norms could be used as well. A global colour standard, CIE is an independently controlled colour standard.

Years of research and tests carried out locally in South Africa validated that a mill can reliably across a number of mills, quickly and accurately grade batches to known "Standards".

To day this is a widely used accurate practice for precise and communicable colour grading data

As us for more at www.narich.co.za