words and image source/photographer : Eksovichea Tito Hak

It doesn't cause any degradation of image quality. So if there are any flaws they're from the original pancake lens itself. It pretty much does exactly what it says, its converts the pancake lens into an ultra-wide angle lens at what should be 10mm without going all fisheye effect. Sure, a decent DSLR ultra-wide angle lens might give you better image quality, but getting something like that for a DSLR at arounf f2.8 would weigh in at about 500 to 600GBP for an appropriate high IQ lens alone, possibly even more. Basically this ultra-wide angle converter for the NEX mirrorless in combo with the pancake lens was exactly what I was looking for to serve as a decent quality interim ultra-wide angle lens solution with very pleasing results for a price that's highly affordable.

Above is a picture of the converter attached to the pancake lens next to an 18-55mm kit lens for scale comparison on the physical dimensions front.