Updated with Zeiss' answer as to why the first lenses are a 35mm and a 50mm.

Carl Zeiss today announced two lenses in its new Loxia line of full-frame, manual lenses for the Sony E-mount, most notably the Sony A7, A7r and A7s: the Loxia 2/35 and the Loxia 2/50, a 35mm/f2 Biogon and a 50mm/f2 Planar.

The lenses closely match the two existing FE primes for the Sony A7-series, the 35mm/f2.8 and the 55mm/f1.8, which also carry the Zeiss logo but which offer autofocus but lack the aperture ring, the metal body and the weather sealing that the Loxia line offers. The Loxia lenses also have an aperture de-click feature for video production.

Still, it's somewhat of a mystery why Zeiss chose to introduce two lenses with identical reach as the two Sony Zeiss lenses, both of which are highly regarded in their own right. Surely, Zeiss would have immediate success if they instead offered prime wide angle lenses for the A7 series.

Update: I couldn't leave the mystery alone, so I asked Richard Schleuning, Senior Director, Americas for Zeiss' Camera Lens Division for a clarification. This is what he replied:

"The goal with the new Loxia family was to develop a new lens line that can be used for both still photography and for video. We will not compete with the existing Sony/Zeiss branded AF lenses for the FE mount, since they are already well received for still photography. However, there are limitations to using an AF lens when focus pulling and in this regard, the Loxia lenses will provide better control. We've incorporated a manual iris on the lens (which is unique to E mount lenses) and the user has the option of 'de-clicking' the f/stop detents to allow for continuous aperture control."

"We started with the 2/35 and 2/50 first, since these are the most popular focal lengths for video. The 35mm focal length is also the most popular among rangefinder shooters - especially street shooters, who we will target with this new lens line as well. Zone focusing will be a snap when using the focus and DOF scales on the lens - also unique to E mount lenses."

"Of course, there are customers who will adapt their M mount lenses to use with the A7 series, but these do not offer any direct communication with the camera and have to be used 100% manually. The price of the Loxia lenses (which includes a lens shade) is less than the cost of a M mount lens + adapter + shade. So there is both convenience and a cost savings to the customer."

"We'll add to the family in the future with wide-angles and short telephotos. The challenge with these mirrorless cameras is designing an ultra wide angle lens that does not exhibit vignetting, lens shading and the 'smearing' effect common when using adapted wide-angle M mount lenses."

In summary, Zeiss is clearly aiming these lenses at video shooters and the Leica M plus adapter crowd. Mystery solved.

The new lenses will be featured at the upcoming Photokina trade show in Cologne, Germany.

That bird above this post is a Loxia, by the way. Zeiss has made it a habit to name its lens lines after bird species.

These are the lenses: