Maybe it is the same reason that is discussed here that causes the greenish tint of the hotspot, caused by the short reflector.
Let us know how the tint is with an older XHP50 emitter once you’re done 
Maybe it is the same reason that is discussed here that causes the greenish tint of the hotspot, caused by the short reflector.
Let us know how the tint is with an older XHP50 emitter once you’re done