35w or 55w, Which is Brighter? Color Shift and Lux Explained
Pop quiz: which HID color is brighter, 4,000K, 6,000K, or 10,000K?
If you do not know the answer, keep reading. Today, I will go over how an HID gets its color and what changes when you go from a 35-watt ballast to a 55-watt ballast.
Color
There are three main things that you probably do not know about HIDs and their color and their brightness.
The first one is how do they get their color? Many people are confused about the Kelvin scale: 3,000K, 4,000K, 6-8-10,000K, and 12,000K. The letter K stands for Kelvin.
The way the HID bulbs get their color is that inside the HID bulb, there is a tiny glass capsule, and inside there, it is filled with a mixture of chemicals and metal salts. Engineers that produce the HID bulbs can change the color by changing the mix of chemicals inside.
The second thing that attributes to the color is your ballast.
Most HID bulbs have a tag on the cord, and you can see it says 35 watts, 5,000K, and then the bulb type. This one happens to be 9007. This label means that at 35 watts, the chemical mixture inside this bulb creates a 5,000K color.
It does not mean this bulb is only rated at 35 watts. You can put a 45 watt, a 50 watt, or a 55 watt HID ballast to power this bulb, and it is still going to work. The bulb tag that says, "35 watts, 5,000K" is just talking about color.
At 35 watts, this bulb creates 5,000K color. If you take a 35-watt ballast, like this HYLUX Slim Ballast from GTR Lighting (shown below), you are going to get the right color on the bulb's label.
So here we have 12,000K Purple, 10,000K Deep Blue, 8,000K Iceberg Blue, 6,000K Diamond White, 5,000K Pure-White, 4,300K OEM White, and at the end, 3,000K Golden Yellow.
If you are using a 35-watt ballast, that means that the ballast only draws 35 watts of power, determining how bright the bulb gets. It also means, at 35-watt ballast power, your bulbs are going to look how they are supposed to look.
You can put a 45, a 50, or a 55-watt ballast on your bulbs too, and all that's going to happen is they will get brighter and have washed-out color. If you use a more powerful HYLUX Ballast, you will go from maybe a 10,000K color, and that same bulb will do 8,000K.
Every time you increase the wattage of the ballast powering your bulb, the color shifts down. So, a 6,000K bulb will look more like a 5,000K. A 5,000K bulb will look more like a 4,300K.
Brightness
The other thing that's going to happen is the brightness increase. You will get about a 50% brightness increase by going from a 35-watt ballast to a 55-watt ballast. So the 8,000K HID bulb will go from 1,000 maximum lux to 1,500 maximum lux at 25 feet, but the color will shift to a 6,000K color.
Just because your HID bulb says 10,000K or 12,000K does not mean that it is brighter. These two 4,300K and 5,000K are the two most brilliant options, both on 35-watt ballast power and 55-watt ballast power.
If you go to the 3,000K color, you lose brightness. If you go to 6-8-10 or 12,000K, you lose brightness also. It only gets worse the further up the scale you go.
Look, the color of the sun is 5,800K that's 5,800 Kelvin, and it is the brightest light source that we know. The further you deviate from that 5,800K natural light, the less usable light you get when it comes to HID and LED lighting. When you get down to 3,000K, it gets closer to the infrared spectrum of light, the red and the yellows. When you get up to 10,000 and 12,000K, you get up closer to the ultraviolet range of usable light.
So, it makes sense. Can you see ultraviolet? No. Can you see infrared? No. So you are stuck in the middle.
I do not mind if you want to do an 8,000K or a 6,000K HID kit, personally if you want to get a specific bluish color. I want you to be aware of what you are getting. Just because it is a higher Kelvin rating does not mean it is going to be brighter.
Lux Testing
We backed these projectors up to 25 feet from the wall, used a digital lux meter to measure the actual, usable brightness at the maximum intensity of the hotspot of each beam, and tested the difference in light output and color between 35 watt and 55-watt ballasts.
The 3,000K Golden HID measured 350 maximum lux with a 35-watt ballast. It jumped up to 490 maximum lux with 55-watt ballast. Aside from about a 50% increase in brightness, the color shifted.
Next up is the 4,300K HID bulb.
At 35 watts, this thing came in at 1,070 maximum lux. That is three times brighter than the 3,000K. When we put a 55-watt ballast on it, it jumped up to 1,510 maximum lux.
The 5,000K HID bulb, at 25 feet, came in at 1,140 maximum lux with a 35-watt ballast. When we powered it with a 55-watt ballast, it jumped up to 1,430 maximum lux.
The 6,000K HID bulb created 986 maximum lux with a 35-watt ballast, and it looks like a 6,000K color. When we put the 55-watt ballast on it, it jumped up to 1,350 maximum lux, but the color shifted down, looked more like a 5,000K.
The 8,000K HID bulb came in at 970 maximum lux. This result was a surprisingly small step from the 6,000K we just tested. Even though it is significantly bluer, the brightness did not change a whole lot in this test.
When we put a 55-watt ballast behind the 8,000K bulb, the brightness jumped to 1,340 maximum lux, and the color shifted down to look like a 6,000K bulb.
The 10,000K Blue HID came in at a maximum brightness of 750 lux with a 35-watt ballast. When we put the 55-watt ballast on, it jumped up to 890.
Lastly, this 12,000K Purple HID made 420 maximum lux with a 35-watt HYLUX Ballast. This 12,000K Purple bulb is the second-worst brightness of the bunch. When we gave it 55 watts, the brightness jumped to 570. When we put the 55-watt ballast on, it jumped up a little bit to 890.
So, what did you learn? You put a 55-watt ballast on a bulb, and the color changes or the brightness increases. 12,000K is not good at all. 10,000K is not bright, and the best colors are in the middle.
I have another pop quiz question for you.
Why do we use Kelvin, the K numbers, a temperature scale to describe the color? If you do not know that, go check out the other video, where we go into that information in depth.
I'm Chris, with Headlight Revolution. I hope you learned something. If you want to see product reviews for automotive lighting, comparisons, or more education like this one, subscribe to our channel so you do not miss what we come out with next. If you have any questions, reach out to us at headlightrevolution.com.
