– Olympus lenses | 4/3rds blog
During 2006, Olympus tinkered with the lens designations again. The terms are now, ’standard’, ‘pro’ and ‘top pro’. I’ve stuck with my labels of consumer, intermediate and professional – which describes lenses according to their specification and not their performance. Consumer lenses are those which appear to be built down to a price; have unexciting specifications; or which generally would not be the first choice for picture quality. Features which get a lens put into this category include poor maximum apertures, rotating front elements, lack of special elements or cheaper build quality. Professional lenses are those which appear to be specified to meet the demands of exacting users. Fast, non varying maximum apertures, dust and water protection, and super special glass are expected. Weight and cost penalties mean that these lenses are not necessarily the best in practice, even if they would produce better results if you could afford them and carry them to the subject. This leads to my intermediate category. Not as good as the professional lenses, but lighter and cheaper. Better than the consumer lenses but more expensive and heavier.
Amusingly, Olympus changed the lens classification names again at the start of 2007. They are now ’standard’, ‘high grade’, and ’super high grade’. I’m sticking with the names I’ve used for the last couple of years.
ED glass – lenses not labelled with the ED designation have “ordinary” elements and might have “Ultra High Refractive Index” glass elements or aspherical ones. Lenses with the ED label additionally have ED, Super ED or ED aspherical lens elements. Olympus is a bit shy on saying exactly what ED stands for prefering to use words like “luxurious”. The distinction probably has more to do with marketing than engineering (in the same way that aspherical used to), but generally read it is a statement of intent about imaging quality.
SWD stands for Supersonic Wave Drive, or, more prosaically, a faster autofocus system.
