Ever wonder, how old your Canon lens is? It’s very easy to find it out using Canon Date Code. Not all, but most canon lenses have a date code located at the back of the lens (lens mount) in a particular format like “UY1013″ (left image).
The first letter is the Factory Code, indicates the Factory where the lens was made. Before 1986, this letter was at the very end of the code. In this example “U” indicates Canon’s Utsunomiya Factory, Japan. Likewise, if your lens date code starts with “F” indicates Fukushima Factory, Japan & “O” means Oita Factory, Japan
The second letter is the Year Code, indicates the year of manufacture. Every year Canon increments this letter. They started with A in 1960 and made it to Z by 1985. In 1986 they started again at A. In this example “Y”, means year 2010. Here is a chart to make it simple…
|Canon Date Code Chart|
The first two numbers [in this example "10"] indicates the month, the lens was manufactured. For example, 01 means January and 12 means December. Sometimes the leading zero of the month code is omitted.
Last two numbers “10″ are unknown, have no role in determining lens age & occasionally omitted.
Now, applying the formula on above Canon EF 135 f/2 L Lens’s Date Code “UY1013″ we can say, it was made in October 2010 in Utsunomiya, Japan .