While listening to some 365 days of Astronomy PodCasts while grading today, I listened to one on Red Light and Night Vision. The author has the podcast as an article on her website located at http://www.alicesastroinfo.com/ . She sites a US Navy study from the 1980's to lead off the article: "Red light has been used because it is well established that subsequent dark adaptation is faster than with any other color. However, the magnitude of this advantage depends on the intensity of the adapting light. … The measure that has typically been used to show this phenomenon is the time required to detect pinpoints of light at absolute scotopic threshold–that is, the individual’s maximum sensitivity. Although this is undoubtedly of great importance at times, it is probably true that in most practical situations the observer is required to operate at something less than maximum sensitivity and to detect targets quite different from spots of light." Alice further quotes a website located here on the myth of the Red light: http://stlplaces.com/night_vision_red_myth/ "Experimentation shows a L.E.D. with a peek around 700nm seems to work best (perceived as a deep red). Note that red may be fatiguing to the eyes." Alice also states that based on the US Navy's stud, one must be fully dark adapted for a red light to benefit and that using a red light source helps "but only if you’re going stargazing in an extremely dark place. If you’re stargazing from within a city, you will likely never be somewhere that dark." I invite anyone to look at the sites, they are interesting I think. So what color light do you use when you observe in your backyard? Is it red, is it white or something else? What light do you use in the field if you need one? Does using a red light really help at a site like SPOC or a backyard where there is so much white light coming into the field from the surrounding neighborhood? Can such sites truly allow for full dark adaptation? I have my opinion but would like to see what others both do and what their opinions are.