My discussion of the quotes and the photo:

"... all images are polysemous; they imply, underlying their signifiers, a 'floating chain' of signifieds, the reader able to choose some and ignore others" - pg 274
Here, Barthes is saying that every image is open to dozens of interpretations - but there isn't one single "ultimate" meaning, they are all correct. With this photograph from
The Sopranos, several explanations appear. One could assume that the man in the foreground is a New Yorker because he is standing near the Statue of Liberty. One could also suppose that he is an immigrant, or comes from an immigrant family, as the Statue of Liberty is located on Ellis Island - the first destination of many immigrants from the past. Another interpretation could be that the man is a businessman, or perhaps attending a special occasion, as he wears a fine suit. The possibilities are endless, and depend entirely on the context during which the viewer sees the photo.
"The text helps to identify purely and simply the elements of the scene and the scene itself; it is a matter of a denoted description of the image (a description which is often incomplete) or, in Hjelmselv's terminology, of an
operation (as opposed to connotation." - page 274
We can use this quote to further make sense of the above photo. The only text of the image reads: The Final Episodes: April 8, 9PM. Made in America." Notably, it doesn't give any information about what television program it's advertising; rather, it lets the actor (as well as the tone of the overall photograph) stand in as a symbol of the show. The first line is simply information about the show, it will air April 8 at 9pm. The next line isn't so easy to define. It could be referring to the show itself, to the actor, to the family (the Sopranos), perhaps to the city behind the actor. In any case, the phrase itself could be inferred to project value on the show - Americans particularly prize products "made in America," because it implies that the products are of a superior quality due to their origins in the United States.
"... there nonetheless remains in the photograph, insofar as the literal message is sufficient, a kind of natural
being-there of objects: nature seems spontaneously to produce the scene represented." - pg 279
Here, Barthes is saying that photographs give a sense of reality that any other medium sorely lacks. When we see the picture of Tony Soprano, we know that he (or actor James Gandolfini) has stood there at some point in time - he is real. We can believe that