CONTEXT The human body emits ultraweak photons. It has been demonstrated that feedback regulation of ultraweak photon emission from the hand is detectable utilizing gelatin color filters in complete darkness. Color filters are commonly utilized in auriculomedicine diagnostic procedures based on the radial artery vascular autonomic signal. OBJECTIVE To evaluate the possibility of an effect by a dark-adapted red filter on (1) local ultraweak human photon emission using different anatomic locations, and (2) on systemic photon emission using one location for red filter exposure and another for photon emission recording. DESIGN Photon emission of abdomen, forehead, palm, and dorsum of the hand was recorded before and after the presence of a red filter. In addition, photon emission of forehead and dorsum of the hand was recorded before, during, and after the presence of the red filter close to the palm. In both instances, the filter was dark-adapted and placed in close proximity to, but not touching the skin of the dark-adapted subject. A low-noise, end window photomultiplier for recording ultraviolet and visible (200-650 nm) photon emission (with a very low background count rate) and designed for manipulation in three directions was situated in a dark room. The technology was utilized to record spontaneous photon emission of the abdomen, forehead, palm, and dorsum of the hand of one human male subject. RESULTS Data demonstrate that a dark-adapted subject responds in the total absence of light with a temporary increase in photon emission from the anatomic locations that had been exposed for 200 s at a distance of 3 cm to a dark-adapted red filter. Data from sequential time series suggest red filter initiation of a refractory emission reaction. Exposure of the palm to the red filter also evokes photon emission from the dorsum of the same hand and from the forehead. This response could be registered immediately after the beginning of the exposure. The stimulated emission is followed by a slow decrease of emission in the period after exposure to the filter. CONCLUSION Data suggest that red filter-stimulated photon emission response is systemic and rapid. Data imply an exchange of information vis-à-vis light from both hand and red filter. The mechanism of such interaction is currently speculation only.