We have found that the HeNeAr and quartz comparison lamps in the rotator guider of the Blanco 4-m telescope provide adequate illumination of the IRS slit and collimator. Because of glass in the optical path they are not very useful beyond 2.2 microns, however. To feed light from these lamps into the IRS you must first place the rotator mirror into beam using the command min. The comparison lamp (HeNeAr or Quartz) must be selected manually up at the rotator/guider in the Cass cage and neutral density filters can also be inserted. Also verify that the lamp power supply in turned on and the control is set to remote. Ask Observer Support for help if you are unfamiliar with the comparison lamps. To turn on the selected lamp type lamp1 or lamp2. [Note: the thermal background from the glass envelopes of the lamps is high at K, making lines in this band region difficult to distinguish from the continuum. This problem can be dealt with fairly successfully by turning the lamp on only a second or so before initiating the integration. We have written a command fastlamp which turns on the lamps and immediately runs a go and turns the lamps off again that should be useful for this case.] The command mout returns the rotator mirror to the normal position out of the telescope beam. The command lampsoff turns off both lamps.