shortens the focal length of your lens by a factor 0.5. expectant believes. I have a part for my Nikkor 35mm ordered because I love this lens and only sometimes they deplore the small image. So I thought to myself, so that I come to 17,5mm .na well with some compromises, perhaps to 20mm. Nix. Screwed the wide attachment in front and there is at first glance is actually a hell Blickwinkel.dumm only that the autofocus does not join in and on distance - infinity - can not focus. Even manually is not möglich.Ist somehow logical. The lens is constructed so that the image is exactly on the sensor. Screwed to a minus lens in front of it, then the image is shifted to the rear and is just for the sensor no longer accessible. I happened to have just ordered intermediate rings. the 12er wins the Focus works again. With the proviso that now (not measurable, but can be estimated) about 25mm focal length are left, with the result that is lost through the now necessary use of the intermediate ring light and aperture 1.8 is pretty much a waste. So I keep it as it is still better maps than a lens that starts at 18mm field with aperture 3.5, but that really would it really is not. must always know himself.
