Hi
finally finished processing this one! Abell370 has a vast gravitational arc that is visible even though the primary galaxy cluster is about 4 billion light years away. The galaxies that feed light into the arc are about twice that far away (ie these photons started travelling this way well before the sun existed). Australian seeing is not too flash for this sort of work, so an early image from the 8.2m VLT is included for comparison and identification of features.
http://www.astrobin.com/full/246996/None/?real=&mod=
In addition to the main arc, I think that I can just make out a second one (it is directly below the main arc and near the bottom of the frame in the ESO image). Although the second arc is right down in the noise, there seems to be a weak linear feature in the right location.
thanks for looking. regards Ray