In the article about the holy (yes now with one "l") trinity of lenses I mentioned my wide lens. The Panasonic Lumix 14mm f1:2.5 (28mm on film). I was surfing through YouTube and found a video about the Panasonic DMW-GWC1 wide lens adapter with a magnification of x0,79. A look on Amazon showed a price of 125€, much to expensive to test but I was now interested in that kind of lens.
The 14mm has a filter thread of 46mm, well what Amazon could offer here? I found one for 18€ (LINK) with a magnification of x0,45 and ordered it. 3 days later it arrived as promised.
I was a little worried if it will cover the complete sensor, without black corners. And if the quality is OK. Well both is good, no black corners and good quality. The only downside, you can't mount it to your lens without the MACRO lens. Why? The lens as a inner thread not the needed outer thread, but you can shoot to infinity with the macro adapter, so who cares? OK, looking on a large screen to the photos with extra lens you will clearly see that only the centre is sharp :( But I would keep it its fun to shoot with this combo :)
The 0.45 factor would give you a 6,3mm lens. I think it is not more than a 10mm but I can not compare it to a real value. Compared to my 7.5mm fish-eye it is not as wide. so I think 10mm ore even 12mm is realistic.
And some more
Photonerd, 36 years old, Mirco Four Thirds Shooter.