What pancake lenses are available for Sony NEX camera?

Question

As a DSLR owner, I am currently looking for a compact interchangeable lens camera and I currently hesitate in buying the Sony NEX-5N or the Panasonic GX1.

I realize the lens options for the Micro Four Thirds cameras are great, and are somewhat limited for the NEX cameras.

Apart from the Sony NEX 16mm f/2,8, do I have other options for a pancake lens?

Answer

Some lenses meant for other mounts can be used with help of adapters. For example, Zeiss Planar 35/2 for Contax G. With a Pentax adapter, you could use the Pentax DA Limited line pancakes (21mm, 40mm and 70mm). Pentax, Canon or Nikon adapter would let you use Voigtländer's Ultron 40mm f/2 or Color Skopar 20mm f/3.5 with corresponding mount.

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