Lyric discussion by tjphoto 

First, as some of the listeners seem to know, Kodachrome was a color transparency film (not a camera, as one commenter says) that had a highly saturated color quality. So it essentially enhanced the color of whatever was captured, though it was also a tricky film to use because of its low ISO rating that is harder to get proper exposures with, especially in low light. Simon may not have known much about it but clearly understood its way of enhancing the look of the world.

As others have said, this plays into the theme of the song, referring to how our memory and nostalgic recollections tend to inflate or enhance the reality of the situation as it was. The first stanza, though, has a further commentary. School and imposed values tend to rob us of imagination and create uniformity.

The camera can capture and enhance memory, but it can also reduce the moment to a flat and cheapened experience. It's the quality of the specific Kodachrome film to enhance the scene. The song is NOT about a drug experience; that's reading into it what is not in the lyrics, though like certain drugs imagination can bring increased vivid experience. The jaunty, upbeat quality of the music is like the quality of Kodachrome, boosting the quality of the experience while somewhat disguising the undercurrent of depression caused by the world as is (without imagination) and the singer imploring "mama" not to take away his means for making life a bit more cheerful.

So it's a playful song at one level, but a more thoughtful and meaningful song under the surface of its fun, upbeat musical quality.

@tjphoto I agree; this is about the unmatched color saturation of Kodachrome film. If you grew up with Kodachrome prints (as I did), you'd understand.

Few things in real life ever seemed to match the intensity of a vivid Kodachrome moment. The gold standard of our best moments, the images that would make you smile on your deathbed.

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