The 60/4 is apochromatic from ultraviolet (315nm) to 1100nm, an almost unprecedented capability that allows focusing in visible light for perfect ultraviolet and infrared focus. It actually transmits from 290nm to 1500nm, should you have the specialized equipment to work in that extended range.
Unfortunately, a camera modified for infrared use that that has had its focus adjusted to accommodate everyday banale Canon and/or Nikon lenses will need “unadjustment” to realize the matched focus of the 60/4. That includes my Canon EOS 5D-IR which “front focuses” with the 60/4. (For more on infrared see the diglloyd Guide to Digital Infrared Photography).
Fortunately my D70-IR focuses quite accurately with the 60/4. Those willing to spend US$4495 on the 60/4 might as well consider dedicating a digital SLR to it, modified for ultraviolet and/or infrared such that the remarkable APO focusing can work its convenience. It would certainly be lovely if Coastal considered producing 28mm and 100mm and 200mm alternatives as well. Especially if they could get the price down to about half of where it is now.
Fluorite lens elements and advanced 12-layer coatings contribute to the unique capabilities of the 60/4 (there is simply no other lens available today from Canon or Nikon or Leica or Zeiss that can perform this way). Watch this blog for more in the coming weeks.