Ned,

I always shoot slides and scan them myself using a Nikon Coolscan 4000ED scanner that will deliver scans at 4000 dpi if I want to do an enlargement. At that resolution, you can actually throw away data points to do a 12x18 print! Personally, I've not found the scans done by commercial processing labs and delivered as PhotoCDs to be satisfactory for most of what I do.

Gary