Some photo variants can sell for big bucks. Prior to 2016, the photo variants were EXTREMELY hard to get. The 2013 variant is by far the hardest to track down. Often times it will sell for $50+ and has even reached near triple digits.
The code on the back differentiates the base from the photo variant.
The 2015 is fairly hard to find and is normally a $30+ card
Unlike the 2013 and 2016 variants, the codes match and don't have any distinguishing features on back to signify it's a variant.
Topps has been making more and more photo variants as they realize there is a market for these short prints. The 2016 version is only a $10 card at best. The photo used for the variant features the same image as the base Allen & Ginter.
The photo for the variant features the same fielding image used for Allen & Ginter.
It hasn't been announced if Cutch will have a Short Print photo variant this year or not. Early signs point to yes though.