We have a photo of my grandfather's brother, it is actually two photo side by side. Face and upper torso. It is sort of like the photos that when we were kids...you put money in the meter and sit in a booth and photos would be taken. It is not a professional photo. I was wondering if you ever heard of a photo being taken for the WW1 registration? What other reason would you have these side by side photos take....he's wearing a suit so can't be a mug shot. Was a photo ID needed for traveling abroad?It's hard to know for sure without having an expert date and identify the photo type, but here is some information that you may find useful.
To my knowledge, no photos were taken as part of the WWI draft registration process. Passports were also generally not required for U.S. citizens prior to 1941, but there was a period during WWI (1918-1921) when they were required that fits your general time frame. According to the National Archives, photographs have been required with passport applications since December 21, 1914, so the photo could have been one taken for this purpose. Or it may have just been taken for fun!
As for the automated photo machines, that is also a possibility. Mathew Stiffens filed a patent for an automatic photography machine in 1889. Monsieur Enjalbert also demonstrated a similar machine at the Exposition Universelle in Paris that same year. These automated coin-operated machines were used to produce instant tintypes for use as souvenirs, ID's and tokens of affection. Although these types of automated photography machines were notoriously unreliable, they were popular until after WWI when, in 1925, Anatol Josepho patented his 'Photomaton.' In 1927, the 33-year-old Josepho epitomized the Great American Dream when he sold the rights to his invention for $1,000,000. His machine -- the first mass-produced photobooth -- quickly made an appearance in amusement parks and other public locations.