Originally Posted by mithrilG60

AudiWorld



Exactly. A yellow colour band in operation is completely normal for stock lights. As I mentioned earlier, it's from the diffraction of light bending on the edge of the cutoff shield. The colour of that band is dictated by a bunch of factors including distance of the shield from the back of the projector bowl, shield shape/curvature and the lens type. However the colour has nothing to do with the health or age of the bulb.

Similarly the clouding of the capsule with salts indicates nothing more than the capsule has been used. HIDs work by using electric current to vapourize salts in an enclosed capsule, super heating them to plasma. The plasma emits light at a specific wavelength (ie. colour temp) defined by the composition of the salt mixture. When the current is turned off the plasma cools and the salts recrystalize. The cloudiness is just finely crystallized salt which will again turn to plasma the next time the bulb is energized.

Originally Posted by mithrilG60

AudiWorld



Exactly. A yellow colour band in operation is completely normal for stock lights. As I mentioned earlier, it's from the diffraction of light bending on the edge of the cutoff shield. The colour of that band is dictated by a bunch of factors including distance of the shield from the back of the projector bowl, shield shape/curvature and the lens type. However the colour has nothing to do with the health or age of the bulb.

Originally Posted by ajg617

When you refer to the yellow band, are you referring to the color of the entire beam, or the yellow band across the top of the beam for example when facing a wall with the lights on? My C6 doesn't have the yellow band across the top - neither do the new Philips bulbs I put in the C5 (the old ones sure did as does my wife's B6). Not to confuse the complete change to pink of the old C5 driver side bulb which would either come up pink or not come on at all.

Originally Posted by jcman

I've recently read an article about the quality of the salts or lack of and the inner bulb shape, salts that have brown flecks are lower quality unless that would have something to do with the color?

Then the shape of the inner salt capsule being manufactured cheap or non conforming compared to premium bulbs that create more heat.

Originally Posted by mithrilG60

It probably has nothing to do with the colour, but it does affect the quality of the bulb. The cheap eBay bulbs tend to cut corners on materials, that's why they're not as bright as real 85122+ or CBI's and it's also why they fail much faster. There's no need to pay stealership prices for bulbs but there is a certain degree of "you get what you pay for" too.

Originally Posted by mithrilG60

I don't profess to be a guru, I just did a lot of research when I was looking into upgrading my projectors. The colour cutoff comments was aimed more in response to ajg617, sorry if that wasn't clear. All HID bulbs will colour shift into the violet range as they start to die; so it makes sense to see pinks in them as they start up. If you leave it long enough the bulb just stays pink, in my area that seems to usually be seen on first gen X5's. Seems they're devalued to the point that any maintenance just isn't worth in anymore.