There are an assortment of preferences when it comes to the luminous coating that lets us keep track of time in lower light. The appreciation of lume does not end at its functional purpose and has stretched to its looks as well. You would think that lume is a one size fits all, but the range is quite varied with your green and blue lume being the most common. Lets take a look at some of the strongest lume varieties available.
What determines the strength?
Luminous coatings used to be made using radium which famously caused disastrous health issues in the 1920s. This used to be the strongest form of light emission that could be harnessed on watch, but the industry has made some great strides in the decades to follow its banishment. Luminescence is charged by light and due to this once it is dark the lume will be bright and will slowly lose charge over time, typically lasting 7 – 10 hours. This type of lume is still painted on as opposed to tritium lume which is instead small tubes of self-glowing radioactive substances. While tritium is more robust and can be made into a range of colours it is definitely not stronger even though it lasts for a longer time and also doesn’t need light to power it. Ultimately the strength of the luminous layer comes down to the watchmaker and how many layers they decide to paint on to their timepieces such as the Lum-Tec team using up to 8 layers on their watches.
Do the colours matter?
In short, yes, the colours do matter but it is not that simple. There are specific kinds of lume that give off different colours and carry different strengths. The C3 Superluminova tops the group at 100% relative brightness and gives off a green/yellow colour. The next closest is the BGW9 which is the light blue lume that we have come to know. During the day it carries a whiter colour. As we move down the scale of brightness found on the Superluminova table we see variations of these brighter colours and the more the colours vary the lower down on the brightness scale they find themselves. If you are looking for something that strays away from the common colours you can expect a reduced amount of strength but it is not likely that you will often need your watch through the entire evening so it is probably best to go with your favourite colour.
When it comes to strongest lume the answer is clear. I do find we can define strength in different ways and if you are looking for something that is longer lasting then you may want to look at tritium lume watches. Watches with Luminova applied vary and when it is applied with greater care can be long lasting as well. If you get regular exposure to strong light, preferably sunlight, then you will be very happy with luminova. I have not made mention to the Lumibrite lume on offer because it is pretty much C3 lume repackaged.