During an outside scan using peripheral vision, illuminated obstacles appear as being further away than they actually are, giving the impression that there is adequate avoidance time.

If the aircraft deviates from the planned route, natural obstacles excluded during the planning stage could be athreat as they could be difficult to see.

Due to the specific wavelength to the colour red, lit obstacles are difficult to identify, increasing the potential for a collision.

Location of aerodromes CANNOT be easily identified unless flying overhead, due to low lightning intensity.