[AZ-Observing] Re: IC 1296

     The galaxy surveysss in the north were done earlier than in the
south, so the data as far as magnitudes is not as good.  In the south
nearly all the reasonably bright galaxies were scanned digitally on
calibrated plates by Lauberts & Valentijn at ESO, so 'pretty good'
standard B (and R) magnitudes are available for close to 15,000
galaxies south of about -20 Dec.  North of the equator one is forced
to rely on Zwicky's magnitudes for galaxies beyond the brightest
few thousand.  All sorts of adjustments have been attempted for
them (they depend on things like the size, which volme of the catalogue
the object is in, and so on...a mess), but without much success.
"More data are required" as the saying goes.  Amateurs could do it,
of course, but it's hard to encourage anyone to bother with it.

\Brian
--
See message header for info on list archives or unsubscribing, and please 
send personal replies to the author, not the list.

Other related posts: