XR what's your opinion on the philips crystal vision ultra bulbs? I've these and seem to have a cleaner white lite output.
There is no such thing as "cleaner" light. In fact, I would argue the light is more dirty. Here is why. The Crystal Vision have a blue tint. What this means is that some of the light is trapped, so not all of the light shines through. This affects your light spectrum. To understand why this is important, you have to consider the question of what is natural light?
Natural light for the purpose of this question is light emitted by heat. For example, the sun, or any other fire. As something gets extremely hot, it begins to glow. Halogen lamps utilize halogen gas to prevent the filament from oxidizing under those extreme heat scenarios, but at the end of the day, it is the heat that produces the light. Any sort of film you coat the lens with will filter out some of that light. In that sense, it may look "whiter," when in reality you are placing a filter on all light except for blue, which makes it "look" whiter to you. However, the net result is a severe loss in output.
How severe? For the purpose of comparison, your stock lamps will be at around 1500 lumens. Philips Xtreme Power were at around 1780 lumens. The Crystal Vision bulbs will sit at around 1350-1400. Keep in mind here that if the tint is noticeable to the naked eye, it is very significant. Our windows are tinted 70%, which means only 70% of light is passed through. Consider those percentages when thinking about total output in lumens. Blue tinted bulbs are a complete scam.
Double the price of the Sylvania xtravision, Sure they might be brighter but is it worth that extra cost? The xtravision is already a great improvement over stock.
What is important to understand is that not all bulbs are created equal. Philips advertised their Xtreme Power as being the most precisely wound filament for a halogen bulb. The end result is a bit surprising. While some bulbs may record a higher output in lumens, the Xtreme Power provides a much brighter focus across the entire light spectrum. I noticed that the sides of the road were better lit than with the Sylvania Xtra Vision, which I ran for one year before switching over. Is the price difference worth it? In my opinion, yes.
