The color that appears blue in the cameras is actually not purple, it’s violet. But these two colours are often confused; especially in Turkey. Because “violet” in Turkish also means a flower of the same name.
In a small-scaled research I made, I found out that the ratio of those who know that violet is also a flower was 1 in 10, and unfortunately there was no one who knew that violet is a different color than purple. In public, violet is known as a shade of purple. That’s why I preferred to use “purple” instead of “violet” in the heading.
I want to quickly mention the event that made me realise this strangeness. Because until that point I myself hadn’t realized the situation.
After Getir was announced as Fenerbahçe’s sponsor, the soccer field advertising boards were going to be colored with Getir’s logo. The big day finally came and as Getir’s logo was being shown, a colleague of ours who is a Fenerbahçe fan shared his excitement with this photo over Slack with the whole company:
Everything seemed normal, but a detail in this photo caught my attention. Main color of Getir’s logo seemed different.
At first, I thought there might be a problem with the camera or the ambient light, but as I got the same results in my own attempts, a huge question appeared in my mind: “Why?”
I knew that the first thing to do was some research. I thought there would definitely be a detailed article about this but I could only find limited information that explained cause and effect. But there must be a satisfying answer to this question. After acquiring some foreknowledge, I determined 5 questions that would help me reach the result:
- What is the difference between purple and violet?
- How do our eyes work?
- Why do people see the color violet?
- Why can’t some cameras capture violet?
- Why can some cameras capture violet?
Now we can start by answering the first question.
What is the difference between purple and violet?
The basic difference between violet and purple is that purple is a color that can only be detected by the brain. On the other hand, violet is an actual colour which can be seen in the visible spectrum. Scientists reached this information by doing observations on the electromagnetic spectrum.
Purple is a subjective color that can be seen with the cooperation of the human brain and eyes. Purple color doesn’t exist in the real world because purple light doesn’t have its own wavelength. It is a mix of the two main colors which are red and blue. Purple light seems more saturated and warmer than violet.
On the other hand, violet has its own wavelength and it is between the colors of blue and ultraviolet. When you break the sunlight using a prism, you can see violet. This special color can be objectively identified with a physical point of view and it’s less saturated and thus colder than purple.
Besides, the color in the rainbow which is supposedly known as purple is actually violet.
In many cameras and color films violet appears blue but purple still appears as purple.
You can try this effect on the color palette above by using the camera on your phone. If you’re already reading this article on your phone, I’m sharing a photo that I took below. But you should definitely try it.
You can more clearly see the difference between the purple colored World logo and violet colored Getir logo. The actual colors of the logos are shown below the photos.
Now that we’ve learned the difference between purple and violet, we can move on to the next question. How do our eyes work?
How do our eyes work?
There are two different photoreceptor cells in our eyes. These are rods and cons. Rods are sensitive to the luminous intensity. They allow us to identify objects when it’s dark. Because they are not as sensitive as cons when it comes to perceiving colors, we see objects as uncolored when it’s dark.
The cons are responsible for perceiving colors. And they operate best when the ambient is bright.The wavelength of light absorbed by the retina and each of the cone cells respond differently, allowing us to distinguish colors. Cons have different types, each of which responds to different wavelengths. These types are:
- Blue cones (S cone cells (S means small), these type responds to shorter wavelengths)
- Green cones (M cone cells (M means medium), for medium wavelengths)
- Red cones (L cone cells, L means long; for longer wavelengths)
Now that we have an idea of how our eyes work, we can reach a more accurate result of our first question by using the information we’ve learned in this article.
Why do people see the color violet?
As a result of a strange response of the cone cells to longer wavelengths, we see the color violet. Yes, the thing that allows us to see this color, stems from a cell response that is strangely named and acts unusually.
To speak more technically, we can say that the cone cells in our eyes respond to short and long wavelength lights, namely blue and red, around 440 nanometers (nm). And this is one of the most important features which allow us to see violet.
Another feature that allows us to see violet is that the L Cones have a strange, bimodal (having two modes) response in long wavelengths(shown with red).
S cones have a broad but well-defined response at the blue end of the short wavelength spectrum. Likewise, M Cones respond to a wide range of propagation on medium wavelength green.
Also, some people can see violet as blue. Although this situation is very rare, its reason is based on some types of color blindness. So if you see a color violet but your friend or customer claims it’s blue, believe them. You can access my other article about color blindness from the link below.
Why can’t some cameras capture violet?
Because sensors are used that cannot imitate the strange response of the cone cells to red light.
The light-response curves of our phones’ cameras are similar to those of the graph above.
You too can compare the reaction time of the cone cells in the human eye and the camera of our phones with the help of the last two graphics above.
Most cameras, including phone cameras, respond to red light in 600 nanometers. That’s why these cameras cannot capture violet.
Why can some cameras capture violet?
Because sensors are used that can imitate the strangeness of the cone cells in the human eye. This enables them to capture violet just like the human eyes can.
The graph above shows the response range of a Canon 450D to different lights. This camera can capture violet because it responds to red light in around 440 nanometers which is almost the same as the human eye. Thus us humans can see violet in images that this camera captured.
In the images below, you can see a photo taken by a camera which can imitate the strangeness of the human eye(on the left), and a photo taken by a camera which cannot imitate(on the right).
Results
- Violet and purple are different colors.
- While purple is a color which doesn’t actually exist and can only be perceived by our brain; violet is a color that exists but can be seen with the help of strange reactions in our eyes.
- Cameras which can respond to long wavelengths like the cone cells in the human eye do (bimodal response) can capture violet. But because these cameras are expensive, cameras that can’t record violet are more widely used.
- Cameras that are used to record soccer matches, movies and high budget movies are professional and expensive so they can capture violet. But if we try to record the violet colors in our television screens, we see that it’s recorded as blue. Because phone cameras are not produced for that purpose.
- Cameras which cannot capture violet can actually record violet to an extent when the ambient light is not bright. Under bright light they capture violet as blue. That’s why these cameras have a high chance of capturing violet as blue.
I haven’t given any information on how these informations could be used in the branding process. But in the branding process this topic must definitely be considered. You can share your comments in the comments section.
Resources
Determining the Camera Response from Images: What Is Knowable? Michael D. Grossberg from Columbia University
The C.I.E Primaries Dr. Rod Nave from Georgia State University
Manufacturer’s reported CMOS sensor responses Cesar Giovanni Chaves from ResearchGate
How does color vision work? on zeiss.com
What is ‘accurate’ color? on benq.com
Difference between Purple and Violet on theydiffer.com
