What does "coupled" mean?

[ulrich.von.lich]

I've seen it a couple of times on eBay:

Leica M39 screw mount, coupled..

Thank you!

Best Regards,
Tony

[Al Kaplan]

It means that the lens is cammed to couple with the rangefinder or the camera's built in meter, or both.

[xayraa33]

I've seen it a couple of times on eBay:

Leica M39 screw mount, coupled..

Thank you!

Best Regards,
Tony

the lens has a cam to couple with the rangefinder arm in the camera so you can properly focus the lens using the rangefinder.

[kuzano]

If the rangefinder or meter are "uncoupled" on a camera, it means that you take the reading from the distance wheel or setting and manually transfer it to the lens to focus or set shutterspeed/aperture for exposure.

"coupled" means that mechanisms (cams or linkages) have been added to circumvent the manual setting phase. On a coupled rangefinder, as the overlapping images merge into one, the lens is focused by the coupling mechanism.

[nikonhswebmaster]

If the rangefinder or meter are "uncoupled" on a camera, it means that you take the reading from the distance wheel or setting and manually transfer it to the lens to focus or set shutterspeed/aperture for exposure.

"coupled" means that mechanisms (cams or linkages) have been added to circumvent the manual setting phase. On a coupled rangefinder, as the overlapping images merge into one, the lens is focused by the coupling mechanism.

They really are not "uncoupled," they are simply "rangefinder coupled" or "not rangefinder coupled" since there are no lenses made that are rangefinder coupled which can be "uncoupled," that I know of.

Some "rangefinder coupled" lenses will "uncouple" when they go into close focus mode, such as the Nikkor 50 mm. They do this because while they can focus under 3 feet, the camera cannot, so the the lens's cam uncouples from the rangefinder wheel.

Not to be picky... :D

[ulrich.von.lich]

Thanks for the education !

Cheers