[rachofsunshine]

Assuming the bands are narrow, that should allow approximately true-color images, shouldn't it?

Human S cone channel = sum over bands of (intensity in that band) * (human S-cone sensitivity in that channel)

and similarly for M and L cone channels, which goes to the integral representing true color in the limit.

Are the bands too wide for this to work?

[nothacking_]

> Are the bands too wide for this to work?

For wideband filters used for stars and galaxies, yes. Sometimes the filters are wider then the entire visible spectrum.

For narrowband filters used to isolate emission from a particular element, no. If you have just the Oxygen-III signal isolated from everything else, you can composite it as a perfect turquoise color.