851px x 315px took place between September 12th, 2012 and November 1st, 2012. Here you can see the collection of images.
The perfomance consisted in collecting a series of images that accidentally fit exactly the dimensions of the Facebook cover (851px x 315px) by looking at a period of time prior to the advent of the Facebook timeline. The images were uploaded day by day.
The motivations behind 851px x 315px were, in first place, to highlight the boundaries that the inteface of Facebook imposes to users, the way in which personal expression is standardized like in advertising banners. Additionally it represented a way to reflect upon the construction of identity that takes place on dominant social media, through a rejection of any personal expression which is substituted by a set of rules (in this case picture dimensions and time span).