Carbine15 is correct.
I mean... I also bought my new Surefire L1 Cree 2 weeks ago and, at first, I became a little disapointed with the green tint on low mode. Before I bought the SF, I just knew Fenix "Ice white cold" lights. I do like my Fenix lights a lot, but now I learned to like this new SF L1 (it´s my first Surefire).
The green tint on mine just appears if I point it on low mode, in a white wall. And lights are not made to hunt white walls. In real use, in real world, I just can´t percept the green tint on low mode (on high mode, it disappears).
And yesterday night I did a test: compared the light of the SF L1 (slightly green) with Fenix L2D (icy white cold). It is more easier to percept COLORS and your variations with the green tint. With the SF (green light) the colors look more vivid. With the Fenix, the colors look a little bit "dead".
Don´t mind about your green tint. First of all, test your SF in real world, and not just in a white wall.
Greetings from Brasil! :thumbsup: