Big Stopper Loc: London

I seem to recall reading somewhere, maybe here on UHH - though I have searched but cannot find it - that the quality of the reversed lens when lens stacking is relatively unimportant, is this the case?

Also, am I right in thinking that the resulting magnification is the focal length of the main lens divided by the focal length of the reversed lens?

I think I also read that for some reason not to use a Canon lens as the reversed lens - can someone clarify please?

Finally, is it important that the reversed lens opens up to a large aperture?

I appreciate that I've asked a lot of questions.

Many thanks, Bob

wierdphotoguy Loc: the snow belt in Michigan

For the first part; it is not as important as it would be if not reversed, but still can affect image quality if it is a really poor lens.

For the second part; this is correct. With a 135mm lens and a reversed 45mm you will get precisely 3:1 magnification. (135/45)=3 If the 135mm is a macro you add 1 to the equation 1+(135/45)=4 because of the close focusing capability.

I use the old manual focus Minolta lenses because there are zillions of them out there, they are inexpensive, and are renowned for their quality. Mike

Big Stopper Loc: London

Thanks Mike, since you posted your reply I've added a couple more questions. Cheers, Bob

Nikonian72 Loc: Chico CA

Your first two questions have been answered correctly above.

Canon lenses can be difficult to rig wide-open, which is required when reverse-stacked to a longer lens (which still has camera-controlled aperture). Also, when straight reverse-mounted, the photographer needs to be able to adjust the aperture, which no longer communicates to the camera. Some manufacturers are easier in this regard, than others. Nikon, for example, has a few attachments with independent control of aperture, so after focusing wide-open, the aperture can be easily closed for photography.

Nikon BR-6 ring + standard cable release = independent control of aperture

Big Stopper Loc: London

Thanks Douglass