1. A method of focusing separate wavelengths of light from a scene, the method comprising: focusing a first set of wavelengths of light onto a detector, wherein focusing the first set of wavelengths comprises positioning at least one lens a first distance from at least one detector; and focusing a second set of wavelengths of light onto the at least one detector, the second set of wavelengths being different from the first set of wavelengths, and wherein focusing the second set of wavelengths comprises positioning the at least one lens a second distance from the at least one detector.