The symmetrized 1.6 cell S-band photocathode gun developed by the BNL/SLAC/UCLA collaboration is in operation at the Brookhaven Accelerator Test Facility. A novel emittance compensation solenoid magnet has also been designed, built and is in operation at the ATF. These two subsystems form an emittance compensated photoinjector used for Free Electron Laser, advanced acceleration and beam dynamics experiments at the ATF. The highest acceleration field achieved on the Cu cathode is 150 fracMVm, and the guns normal operating field is 130 fracMVm. The maximum RF pulse length is 3s. The quantum efficiency of the copper and magnesium photocathodes was measured to be 4.5x10-5 and 10-4 respectively. The transverse emittance of the photoelectron beam were measured for various injection parameters. The optimized rms normalized emittance for a charge of 300 pC is epsilon_n,rms = 0.7 p mm mrad. The bunch length dependency of photoelectron beam on the RF gun phase and acceleration fields have also been experimentally investigated. Beam dynamics studies indicate that the symmetrized 1.6 cell cell S-band photocathode gun has meet its design goal of minimizing the TM_011 component of the p-mode. Show Partial Abstract