Archived posting to the Leica Users Group, 2005/06/22
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On 22 Jun 2005 at 23:19, feli wrote: > The auto stop down in Canon/Nikon lenses isn't just a mechanical > linkage? Not in the EOS line. > Do they really need the electronics for that? Nikon/Canon's old > manual focus > lenses are all mechanical... yes, but they haven't built anything in that line in ... a decade, more or less. The EOS linkages are fully electronic. Aperture settings are dialed into the body and transmitted to the lens at shooting point. There's nothing on the back of an EOS lens or within the mount of an EOS body except contact points. No physical link at all. A mechanical-aperture lens would have to be on the order of a preset lens, like a rangefinder. Any kind of shutter controlled mechanical stopdown won't work without extensive body modification (and I have no idea whether that would even be POSSIBLE but I doubt much that it would be cost-effective.) -- the hardware's simply not built into the body. -- R. Clayton McKee www.rcmckee.com Photojournalist rcmckee@rcmckee.com P O Box 571900 voice/fax 713/783-3502 Houston, TX 77257-1900 dig pager 281/510-3588