On Thu, 5 Dec 2002 09:03:36 +0200, Dr E D F Williams wrote: >I have often wondered about the EX finish on Sigma lenses; its black and >hard. Reminds me of the Teflon based stuff I used to have sprayed on my 45 >colt slides. It was called GunCote and was baked on after being sprayed onto >a finely sandblasted surface. (As a hobby I used to customise hand guns, and >shoot them.) GunCote could be used on any metal and later I had optical >bench parts coated with it. I'm quite sure that lens barrels could be >GunCoted. Perhaps its the same stuff?
Don, I don't think it's the same stuff. If it is then it wears easily. I have a Sigma 105f2.8EX Macro and the finish is wearing on the edge of the focusing ring from being put in and taken out of a camera bag. Apart from that the lens is still in perfect condition. Leon http://www.bluering.org.au http://www.bluering.org.au/leon
