detection unit 206 is a spectrometer the controller can detect a decrease in the intensity of known wavelengths complementary to red orange wavelengths either as an absolute measurement of intensity or relative to spectral bands where absorption effects do not take place controller 208 provides control signals to the conveyor 200 and or the flame unit 204 in response to the output of optical detection unit 206 if the color shift has not occurred within a predetermined amount of time controller 208 can adjust the relative position between the flame and the assembly 202 by slowing the conveyor 200 further controller 208 may increase the intensity of the flame from flame unit 204 once the color change is detected by controller 208 controller 208 can increase the speed of conveyor 200 to adjust relative position between the flame and the assembly 202 and or reduce the intensity of the flame from flame unit 204 this maintains the temperature at the joint the color change indicates that the assembly 202 has reached the appropriate temperature to melt the filler material reducing the heat prevents overheating of the joint and damaging the workpieces while still maintaining the joint at a temperature sufficient to melt the filler material in this manner the controller 208 prevents damage to the aluminum assembly 202 fig4 depicts an automated brazing system in exemplary embodiments an assembly 250 to.