A bit simplified the coatings consists of one or more layers of glass (or similar) having slightly different refractive indexes. Each layer have a thickness corresponding to 1/4, 3/4 (...etc) of a chosen wavelength, thus reducing reflections at this wavelength. Single coatings have one such layer, I think usually green, SMC have 7 (I think I remember) reducing reflections at a number of wavelengths.
DagT
P� l�rdag, 28. juni 2003, kl. 20:44, skrev Boris Liberman:
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
