Way back in undergraduate optics, I was told that reducing the aperture
of a lens mitigates various problems such as spherical aberration, and
of course it makes focusing less critical (aka depth of field). What I
am not sure of is whether a reduced aperture reduces chromatic
aberration. It would seem to me that if you make focal distance less
important, then the effect of red and blue light focusing at different
distances should also become less pronounced.

If I can get a hold of some solar film in time, I would like to attempt
to photograph the annular eclipse of the sun in May and the transit of
Venus in June. The way I see it, I should have plenty of light to
spare, and my camera is probably a long way away from being diffraction
limited, so why not use a small aperture?

The chromatic aberration issue with my camera is really only apparent
when attempting astrophotography. Here is one example:

http://www.flickr.com/photos/3585314...t-721576231290
10923/lightbox/

(view the 1024 pixel version for best results.)

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