Rob is certainly a leader in CCD mosaic work. You may also want to check out Russ Croman site for some equally impressive work -
http://www.rc-astro.com/
I believe Rob and Russ recently got grants from RC Optical Systems and SBIG, hence both now have robotic imaging observatories under dark skies. Put bluntly, its not that they know how to image, they know how to process an image. These guys can make an average image come alive with their digital processing experience. Check out Robs collaboration with Aussie astrophotograph Martin Pugh -
http://www.martinpughastrophotograph...ae/NGC3576.htm. Martin's image is mighty fine, but when you see what processing Rob does to it, it turns out sensational. These guys are not in it for quantity, only quality. 20 to 30 hour exposure times to bring out extreme details are the norm for these two. They are truely masters and leading the way in CCD imaging.