stuff
So what are the found objects in Jasper John's work "Field Painting". First let's take a look at the actual letters. Johns has first incorporated a neon R, which is controlled by a switch on the left hand side of the left panel.
The neon "R" is the only letter the has an "appropriate" color. The other letters have a color that has nothing to with that which the letter describes (ie. the B in "BLUE" is the color orange).
Other found objects in the piece include a Savarin coffee tin, a Ballantine beer can, a 
paintbrush, a soldering spool, and a chain. These objects were not always in the same place. It may be that Johns' original intention was that the users interact with the found objects. Also the letters on the hinges were moved so that their orientation is not the same in every photograph of this piece.
It seems that many of these objects were merely playful, while some of the splotches of paint may have more meaning (ie in the top right of the canvas Johns has included his signature: a footprint).