On Sat, 30 Nov 2002 16:33:46 GMT, Jim Klein wrote:

>Coatings will cut down on multiple reflections which would possibly
>have chromatic aberrations and in this way you could say coatings
>help. It is just that they don't really help the non-multiple
>reflection chromatic aberration to any great extent.
>Jim Klein

Nice in theory, but the reflections would not be focused,
removing their chromatic aberration problem - but even that
is not relevant, since even if the reflected CA problem
were imaged on the film, it would be at a level too low
to register visibly on the film...;-) In other words, forget
coatings as a way to correct CA (unless, of course, they
are applied thick, with controlled and varying thicknes,
and are designed to modify the lens element curvature in
a way that is able to correct CA...;-).