We demonstrate a photon-counting optical-time-domain reflectometer (OTDR) operating at a wavelength of 0.85 microm at room temperature with high sensitivity (3 x 10(-15) W) at high resolution (1.5 cm, 150 psec). Measurements of splice losses and Rayleigh scattering losses less then 0.1 dB with centimeter resolution are demonstrated to be possible with such an OTDR.