What is the brief opening guitar song in the Song Remains the Same Movie? The song that is playing when the concert hall is dark and the doves fly away? I know Rock n Roll is the first song but this is before that....just guitar.

Has anyone seen this “exact” photo of them in color? I have seen the other color similar pictures from this photo shoot but I have never seen this exact one (see attached) in color. You would think if the other photos from this shoot were shot in color this one would be too....idk thanks