I apparently still don't feel like blogging, so here's a pretty picture of a nice galaxy cluster, Abell 611, for you to look at:
This is one of the clusters we're looking at with the LBT for our weak lensing study. A nice example of strong lensing is the pair of blue arcs above and to the left of the center of the image; those are background galaxies being lensed by the cluster.
Some stats for those of you who care about that kind of thing, copied blatantly from the CCAPP webpage which was in turn copied blatantly from the observer who took the data and made the pretty picture:
Details: the image is about 2 arcminutes on a side, North is up, East is to the left. The integration times were 20min in Uspec, 60min in g-SDSS,and 15min in r-SDSS. The image quality in the combined images is about 0.6" FWHM in g and r, but they were smoothed them to match the 0.7" image quality of the u-band image.