> Exactly. How far back in time could you look with a
> 55mm Celestron Fluorite APO refractor?
Well, in the unlikely event that I could do as good a job as Ray,
simple scaling suggests I might lose a couple of magnitudes compared
to his work, which suggests that a theoretical "heart of Virgo" image
taken with Refractor Red would to to about magnitude 18 on galaxies.
It is interesting to note that the individual components of Einstein's
Cross are all brighter than that, though it would take a lot of plate
scale to resolve the cross, as it is less than two arc-seconds across.
But it is eight billion light years away, so it would be fun to try.
Maybe we could all chip in Barlows to stack... (And just for the sake
of not confusing anyone, Einstein's Cross is not in Virgo.)
-- Cosmo Freeman, of the Spaaaaace Patrooool!!