Interesting review.
SLR gear reviews are even harder to compare between platforms than anyone else, because their "blur units" seem to be relative to the best performance of the lens (or possibly the sensor) so they really only tell you about uniformity.
But there is a review of the 55 1.8 which many of us have and find amazing on SLRgear, reviewed on the same platform, so it's possible to compare.
It's pretty amazing. The 35 1.4 is just about as good, a little softer in the corners wide open (as you would expect for a very fast 35 compared with a medium-fast aperture standard lens)
And it outperforms the excellent 35 2.8 at most apertures (also reviewed there on the same platform).
Tempting...
I'm not sure one would need to precisely compare figures for the lenses made for different systems, because very few lenses appear to be cross-system comparable anyways, and the shape of their blur plots is as good as the Photozone bars when you need rough guidance. Therefore I quite like the SLRGear way of presenting sharpness.
The 35/1.4 ZA looks pretty good. Vastly better than the old 35/1.4 G on A900 - that lens looked truly bad at f/1.4 and f/2, with sharpness distribution worthy of a $350 lens but not a $1350 one. But then again, Photozone has found the same thing, even if only on APS-C.
Quote:A very lazy but very effective solution to fixing issues based on the coverglass is to complete the design then vary every radius of curvature with the new coverglass thickness. The optical path is very similar but the balance of astigmatism and spherical must be adjusted - often the optical design software will "smash" the new aberration and recover 90%+ of the old performance.
Do you think it can also work for very wide angles such as Biogon 21/2.8 or even Hologon 16/8 ?
http://flickr.com/ephankim
Depends what with. Can the design be fixed - yes. Can the lens+sensor interaction be fixed, probably not.
Symmetrical wide angles have exit pupils that are quite close to the sensor. The design itself is okay, even the coverglass is okay, but when the pixels get below some size photons end up crossing the entire photodiode and embedding themselves in the wall of the pixel before they are absorbed. This happens more for longer (redder) wavelengths as the tend to not divert from their original path as easily (see: prisms and rainbows) hence the blueshift/color cast in the corners.
The general consensus in the lens design community (to my knowledge) is that bertele's symmetrical wide angles have been obsoleted by digital sensors, which is a shame because they are often rather beautiful designs.
I am a brand new buyer of the a7. After many days of killing myself over all the choices of DSLRs, I got the a7 for a compact, lightweight, and user-friendly device to begin my astrophotography hobby. I am very happy so far with it.
Can I get opinions on what the best FF Wide-Ultra Wide Lens for astrophotography would be? I will eventually be looking to do star trails and move up into huge landscape/Milky Way shots. Ideas?? I am very green, and need to learn it all.
