In article <4j6kg2$g29@hpg30a.csc.cuhk.hk>, smwong@cs.cuhk.hk says...
>In article ,
>Fredrik Kurosh Fatemi wrote: [....]

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>>What it should look like, What I get on the film
>>[without comet :) ]

>Okay, I'm naive enough in astronomy. But from your wonderful ASCII
>photos, will it be that due to long exposure, the earth actually >rotates quite a bit, and therefore, the circular shapes?

Boing!!! Of course! I shoulda thought of that! (Guess I got fooled
by the part about it's not happening with an old [probably inferior]
50mm f1.4 that threw me off....!) So I looked for a defective-lens
solution for my answer in r.p.misc......
Hope This Helps