Archived posting to the Leica Users Group, 2004/11/18
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]DEAR PAUL: Technically, an aspherical lens is a lens whose curved surface does not conform to the shape of a sphere; lenses are usually ground or molded with spherical surfaceS. A spherical surface lens has difficulty in correcting distortion in ultra-wideangle lenses or coma in large-aperture lenses brought about by spherical aberration. When it comes to zoom lenses however it tends to be a bit different, an aspherical lens element or two can substitute a number of lens elements which in the end will achieve similar optical results (sometimes even vastly improved optical results). By using this technique a Lens manufacturer can not only reduce the cost of production but can also decrease the size of the lens itself. This can be improtant in Zoom's especially as they tend to have many more elements than fixed focal length lenses. Most fixed focal lengths have about 6 - 8, whereas zooms can have in excess of 10. Asphericals have been around for ages (but Leica takes things SLOOOOWWWW). Generally manufacturers only use aspherical elements where no substitute can be excepted. Leica lenses however shame on me for saying use them for marketing (shame on you Alex). I however do have an ASPH 35 f2. If you really want to tell the difference........ Examine artwork taken with these two and see what you like, or you could rent/borrow one or both and see if you like one over the other or........ Just buy the one you can afford. I have a 1968 type 2 50/f2 it aint ASPH but I like it even though its the black sheep of the 50 mm lenses, but hey it cost me 350 bucks, my 35f2 ASPH cost a grand (1000) I am not complaining . They are all excellent peices of glass no matter how round they are. Buy what you can afford and shoot, if you really hate it someone else will always buy it for what it cost you. Thats why Leica rocks. Alex _________________________________________________________________ SEEK: Now with over 50,000 dream jobs! Click here: http://ninemsn.seek.com.au?hotmail