Curious as to what you define as basic research your ran across. According to the 1854 US Army Regulations, a regiment was issued a stand of colors, a National Colors, Regimental Colors, & 2 Camp Colors / line colors, which are small National Colors, with the appropriate number of stars. One stand of colors for parade and one for the field. State Troops used deferent standards. So it depends on if your searching Federal Troops or State Troops. Some were a solid color with unit designation or State Colors with unit designation on the field. Depending on the flag maker, contract for a depot or private dealer.
The 1890 U.S. Army Regulation call for the same as the 1854 reg’s.
The (Federal) Regimental Surgeon was the one who marked the set up for Regimental Camps, by regulation he used Camp Markers to mark the area of camp. The surgeon also was in charge of all of the camps activities. State Troops followed State Regulations, if there was not any, some improvised on camp flags.
Only a few Confederate State’s had regulations on camp/line markers. North Carolina used a small red flags, with unit designation painted or sewn in the center.
The National Archives has information on Regulations on Federal Troops. It will depend on which Regiment your researching, some had custom made colors. Most State archives will have data on their State Troops.
I hope this helps in your quest.