A solar cell testing apparatus comprising: an illuminator for directing light energy on a solar cell under test; and a device for selectively positioning different filters of a multiplicity of filters in an optical path between the illuminator and the solar cell under test to at least one of measure performance and detect any defects in the solar cell, the multiplicity of filters comprising a first set of filters , each filter of the first set of filters being adapted for passing a predetermined percentage of intensity of the light energy from the illuminator onto the solar cell under test, and a second set of filters for testing the solar cell under different spectrums of light, wherein the device for selectively positioning the different filters comprises: a rotatable filter wheel with the multiplicity of filters mounted in the rotatable filter wheel ; and a motor for rotating the rotatable filter wheel , the motor including an encoder for determining a precise location or position of the rotatable filter wheel and each of the multiplicity of filters , wherein the multiplicity of filters further comprises a light blocking filter to perform an electroluminescence test of the solar cell to detect light emission from the solar cell in response to an electric current of a predetermined amperage being applied to the solar cell. an illuminator for directing light energy on a solar cell under test; and a device for selectively positioning different filters of a multiplicity of filters in an optical path between the illuminator and the solar cell under test to at least one of measure performance and detect any defects in the solar cell, the multiplicity of filters comprising a first set of filters , each filter of the first set of filters being adapted for passing a predetermined percentage of intensity of the light energy from the illuminator onto the solar cell under test, and a second set of filters for testing the solar cell under different spectrums of light, wherein the device for selectively positioning the different filters comprises: a rotatable filter wheel with the multiplicity of filters mounted in the rotatable filter wheel ; and a motor for rotating the rotatable filter wheel , the motor including an encoder for determining a precise location or position of the rotatable filter wheel and each of the multiplicity of filters , wherein the multiplicity of filters further comprises a light blocking filter to perform an electroluminescence test of the solar cell to detect light emission from the solar cell in response to an electric current of a predetermined amperage being applied to the solar cell. a rotatable filter wheel with the multiplicity of filters mounted in the rotatable filter wheel ; and a motor for rotating the rotatable filter wheel , the motor including an encoder for determining a precise location or position of the rotatable filter wheel and each of the multiplicity of filters , wherein the multiplicity of filters further comprises a light blocking filter to perform an electroluminescence test of the solar cell to detect light emission from the solar cell in response to an electric current of a predetermined amperage being applied to the solar cell. <EOS>