Posted 11 April 2009 - 04:13 AM
Are these basically the same lenses? (Forget the obvious difference in Macro Strength and Brand/ Quality)
Concave - Convex is about all I know about lens shapes.
Posted 11 April 2009 - 05:13 PM
Posted 12 April 2009 - 03:18 PM
No, an achromatic lens has no relation to macro. An achromat is two lenses of different refractive glass (normally Crown and Flint glass) sandwiched together to get rid of chromatic aberration. There are five main aberrations in lenses; coma, astigmatism, distortion, chromatic aberration and spherical aberration.
And when three or more lenses of different refractive glass are used it is an apochromatic lens.
Posted 12 April 2009 - 06:12 PM
Those correction properties and the macro focusing properties are not interrelated in any way. It's not a bad idea to read up on at least basic optics. It will help you to decode the terminology surrounding various types of lenses and their characteristics.