What is color shift?
The labled light color on an HID bulb is an average that it will maintain over 2-3000 hours. After passing around 100-500 hours the phenonmen “color shift” will take place. Color will change slightly from a yellowish tone to a crisper bluer tone. The magnitude of color shift will vary depending on brand, model and rated color. It is a very gradual change and unless paid close attention to, a customer might not notice. OEM 4100K Bulbs manufactured by Philips has been reported to have a more noticeable color shift than OEM 4100K Osram. OEM 4100K Bulbs manufactured by Philips has a colorshift of approx 250K after 500 hours, which will bring it to up to 4350K. Asian manufactured bulbs has been reported to have little or no color shift. Most of them come with output stealing blue filters, which may be part of the cause.
