1. A system for acquiring one or more biometrics of a subject, the system comprising: a sensor to detect a biometric feature of the subject and to acquire two or more images of a corresponding iris of the subject, and one or more infrared illuminators to provide: infrared radiation at a first infrared radiation level sufficient for the sensor to detect a biometric feature of the subject, and responsive to detection of the biometric feature by the sensor, a predetermined sequence of pulses of infrared radiation at a second infrared radiation level greater than the first infrared radiation level, the second infrared radiation level being sufficient for the sensor to acquire the two or more images of the corresponding iris of the subject for biometric matching.