During the flashback 'Hermanos' scene, a warm tint is applied to the picture to give a retro feel to the sequence. What was not accounted for is that the resultant raised contrast makes makeup applied to the actors much more visible. Particularly noticeable are Gus & Don Eladio's pale concealer panda eyes.
This is the first time we actually see who's watching the laboratory spycam -- it's Gus, of course, using the laptop in his Pollos office. But, who is moving the camera? Those security cameras don't automatically track people, but it's been moving like crazy in all the previous episodes, and when we see Gus watching the camera, he isn't manipulating it, but the camera is panning anyway. The other five images are static. However, any of Gus's employees could be operating the camera.
During the flashback scene in the pool, it is obvious that none of the characters are native Spanish-speakers, and most speak with heavy American accents. Neither Fring nor his partner Max, who are supposed to be Chileans, speak with anything resembling a Chilean accent. And Don Eladio speaks with mostly Cuban characters.