You are dealing with three things here, Boris, not two. Uncoated, single-coated, and multi-coated elements.
The Takumar you mentioned is not uncoated, but single-coated, almost all lenses made since WWII were. What coating is is a very thin layer of antireflection material deposited on the lens surface. Multi-coated lenses have several layers each specific to a different wavelength of light. These coatings are usually applied to the glass-air surfaces of the lenses, the cemented surfaces are usually uncoated. This was discovered by photographers who found that their old lenses which had developed a film on the surfaces were more contrasty than new lenses. They called this "bloom". In the 30s much research was done to find a way to do this artificially. To the best of my knowledge, the first consumer lenses to be factory coated were the Kodak Ektars in the late 1930s. In the 60's Pentax and Zeiss developed ways to multi-coat optics resulting in a further improvement. Those two companies still seem to be ahead of everyone else with improvements. Coating only really does something when there is flare in the lens. If there is no flare an uncoated lens works just as well. However in real world photography there is almost always some flare involved. Ciao, Graywolf http://pages.prodigy.net/graywolfphoto ----- Original Message ----- From: "Boris Liberman" <[EMAIL PROTECTED]> To: "PDML" <[EMAIL PROTECTED]> Sent: Saturday, June 28, 2003 2:44 PM Subject: One more question - Lens Coating > Hi! > > Honest, I don't know what I am going to ask <g>. What is the > difference between coated and uncoated lens? I mean lens construction > - do they coat each surface, only front and back element? Also, given > an uncoated lens (such as almost-the-lens Takumar K 135/2.5), if one > attaches to it coated filter (such as Vivitar VMC Skylight 1A), how > much would it lower the flare? I suppose I won't be able to shoot into > the sun like I can do with my SMC FA 50/1.7, but still it is something > I'd like to learn. > > Thanks. > > --- > Boris Liberman > www.geocities.com/dunno57 >
