Upload & Sell: Off
Undoubtedly this lens has a raison d'Ítre despite the existence of a highly regarded Canon "equivalent".
In the following circumstances, the new Zeiss will probably trounce the venerable L lens.
- When mounted on a high-MP full-frame camera. In the following years, 30, 40, 50 MP cameras will flourish, and the Zeiss lens sure was developed with this context in mind, enabling photographers to extract the best from such sensors. This was of course not the case with the 135L. You may not see any big difference if you compare them on a 5D, but how about on the rumored 45+ MP camera ? Time will tell, but the 135 from Zeiss is likely to easily outperform the 135 from Canon.
- When focused at - or near - infinity, on any camera. High end Zeiss lenses such as the 100 Makro-Planar are renowned for being stellar performers whatever the focusing distance is, contrary to the 135L which is not at its best when focused at infinity. Following this, one can reasonably expect the new Zeiss to perform superbly at infinity, making it a fantastic landscape lens - what the 135L is not... and its AF is of no help in this regard.
And no, the new Zeiss 135 is not the same design as the 135 for Sony (which is not an apo). Confirmed here, in the comments.