I bought a 52mm reversing ring to use on my G1 for macro photos. It works fine with the 14-45mm kit zoom. I can focus using the zoom ring or by moving the camera toward or away from the subject, but the focusing ring has no effect and I cannot change the aperture. I thought maybe I needed a manually focused lens, so I got a nice used Nikon 50mm f1.8 manual lens which conveniently has a 52mm front thread. Well, that didn't work. When mounted in reverse, the lens will not focus at all at any distance. So what is my problem? Is there any way I can use the Nikon lens in reverse on the G1? Since the sensor distance is different than a Nikon body, do I need an extension tube between the lens and camera? I am totally confused about this.
The smaller flange back of mirrorless cameras is in this case a disadvantage.
I don't want to confuse you more - so I don't start calculating (you know, this "1/f = 1/b + 1/g" stuff).
Just try an extension tube or bellows attachment.
Following Andreas' suggestion, I bought two extension tubes and tried one of them with the 52mm MFT reversing adapter and the Nikon MF 50mm f/1.8 lens. The extension tube was 21mm long and threaded into the front of the lens with the adapter on the other end of the tube and connected to the G1 body as shown below.
With this arrangement, the focusing distance is on the order of 200mm from the front of the lens (the normal rear element) and the field of view is about 51.5mm by 39mm. The following two shots show a 3D target (ceramic kitty) and a flat plane target (stamp). No post processing was applied other than resizing for posting.
The advantage of using the Nikon prime lens over one of the Lumix kit zooms was that I was able to change the aperture of the lens. When you connect the automatic lenses in reverse they remain wide open.
This is all new to me, so if anyone has experience with reverse macro work, feel free to share your experience and suggestions.