Generally speaking people who scrub lenses (aaaaargh!) to clean them do it round and round and not radially. Radial marks are quite unusual and bear investigation merely because they are such. Lens cleaning is an art and should only be carried out by someone who is a master of that art. One very good way to really _clean_ a lens element is to take it from the mount and wash it in soapy water, Fairy Liquid is good, rinse it in deionised triple distilled water and dry in on edge in a completely dust free atmosphere. There are other ways, but they are rather special. Washing in a reflux chamber with propanol vapour for example. Not easily done by someone outside a laboratory.
Don Dr E D F Williams http://personal.inet.fi/cool/don.williams Author's Web Site and Photo Gallery Updated: March 30, 2002 ----- Original Message ----- From: "Keith Whaley" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Sunday, December 01, 2002 3:24 PM Subject: Re: Basic rule you can take to the bank > Marks that are in a circular pattern are called circumferential, and > marks that start in or about the center of the lens and traverse the > lens surface to the outside are called radial marks. > > keith whaley > > Mike Johnston wrote: > > > > > Interesting. The marks in my lens are radial, ie they go around the lens > > > in a circular pattern and cover basically the whole area of the element. > > > > Pretty much Universally, lens elements should not have marks on them. > > > > --Mike > > > > P.S. I'm hoping this will prove an uncontroversial statement. <g> > >
