(IAAC) Re: light-pollution filters --The Poor Man's Deep Sky Filter
> > The ... DeepSky filter ... is basically a magenta filter,
> > which has TWO passbands, one in the red and one in the blue; while
> it blocks out the yellow-green in between... .
PS: And therefore the enterprising amateur can obtain his/her own
"DeepSky Filter" for US$20 down at the local camera shop, in the guise
of a 48mm Wratten 30 photographic filter. Does fabulous things for
Jupiter! No need to spend $US80-100 for a fancy brand name.
Thomas O'Hara, PhD
San Diego, California, USA
"Blessed are they who expect no gratitude;
For They shall not be disappointed."
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