I'm definitely no lens design expert but I don't see much in common with the Minoltas. However I can see that the front and center groups are very similar between the 2 Zeiss lenses. The rear groups are different though. I'm sure the Suede will chime in soon
The older Zeiss Contax Distagons look closer in the rear optical design to the new ZA (and more like the Minolta) then the current ZF lenses but all these wide angles seem to be different at some point.
it doesn't seem to be that complex of a design. One can see why it only costs around $1250. Are you saying that is is similar to the ZF 25/2.8 (which follows)? http://boncratious.com/images/ZF25.jpg
I don't see all that much similarity, especially considering they are lenses of the same focal length.
When you include the two aspherics they're about equal in design complexity, though the back end would seem a bit more demanding regarding mount tolerances in the ZA. It all boils down to the aspherics, and how they respond to different focusing distances. I haven't seen any close up corner performance yet, but I'm guessing the ZA is optimized for mid-far-field performance. The Zeiss concentrates most of the compression in front of the aperture, whereas the ZA seems to do most of the WC behind the aperture. The new ZA is VERY different from a pure Distagon, both in planning and in execution. It also seems to be more "digital ready" from some points of view.
theSuede wrote:
The Zeiss concentrates most of the compression in front of the aperture, whereas the ZA seems to do most of the WC behind the aperture.
For comparison purposes. Just be aware that they MTF's for these 2 lenses are not directly comparable. The Sony lens MTF's are theoretical calculations (giving you that almost 100% fantasy MTF at f8) while the Zeiss lens MTF is measured from a production lens. Also note the differences in the apertures reported in the MTF's (Sony -- f2.0 and f8.0; Zeiss -- f2.8 and f5.6) http://boncratious.com/images/y_SAL24F20Z_MTF.jpg http://boncratious.com/images/ZF25MTF.jpg
Yes, all I think I can compare is the MTF's at f8 between the ZA 24-70 and the ZA 24 and I don't think the ZA 24 is much better which disagrees with the differences in corner samples on the artaphot site. I think he probably had a bad copy of the 24-70 or there is difference due to field curvature or something.
Hard to compare the ZA 24 at f2 vs. the ZA 24-70 at f2.8.
Just thinking out loud here, but maybe the "redesign" of the ZF 25mm f2.8 is due to Sony not accepting Zeiss' design for the ZA 24mm f1.4. Maybe the "redesign" is just an outlet for their 24/1.4 design Rejected by Sony as too expensive (given their "understanding" of their "target market"), Zeiss turns around and adapts it to their ZF/ZE lines of lenses.
OK. Maybe this isn't "thinking", but more "dreaming". ;-)
Lotusm50 wrote:
Just thinking out loud here, but maybe the "redesign" of the ZF 25mm f2.8 is due to Sony not accepting Zeiss' design for the ZA 24mm f1.4. Maybe the "redesign" is just an outlet for their 24/1.4 design Rejected by Sony as too expensive (given their "understanding" of their "target market"), Zeiss turns around and adapts it to their ZF/ZE lines of lenses.
OK. Maybe this isn't "thinking", but more "dreaming". ;-)
Sounds plausible but I think you maybe dreaming a little for the new ZE/ZF 25 to be f1.4 instead of f2 which is still down from the original f2.8.
If it is f1.4, our Sony Alpha bretheren will be very upset.
Of course FM'er Toothwalker knows but he can't tell us.
Tariq Gibran wrote:
Now that looks like one complex design!
Yep, the 24/1.4 is yet another killer Nikon lens. Zeiss lenses get a lot of attention, but honestly, these days, i think Nikon has got to be the lensmaker that's at the top of their game. To wit:
- The 14-24 is so good that it beats most companies' primes, let alone zooms
- The Nikon 24-70 is breathtakingly good. I had both the Nikon and Sony Zeiss 24-70's, and i honestly feel the Nikon is a better lens. Better corners at 24 mm, more 3D effect, much better bokeh, and better overall rendering
- The 24/1.4 is by all accounts excellent optically. It wouldn't surprise me if it was as good at f/1.4 as the Zeiss is at f/2
- The 85/1.4 saw an already legendary portrait lens get even better
- The 60/2.8G macro is optically one of the best lenses i have used
And the list goes on. Don't get me wrong, i am not criticizing Sony / Zeiss nor am i a Nikon fanboy. I have a full Sony system and at one point or another owned all 3 of the original ZA lenses (24-70, 85, 135). But i do think that with the exception of the 135/1.8, none of the ZA lenses thus far have been truly exceptional (exceptional as in unusually good and superior to the competition), and in fact the ZA 16-35 unspectacular considering what Nikon was able to do with the 14-24 (and the 17-35 for that matter, which is arguably as good as the ZA 16-35 despite its old design).
Basically, i expect more when i hear the name Zeiss. Where is that legendary Zeiss superiority... the IQ that was in a different league compared to the Canikon and Minolta fare of the film era? Remember the Contax G2 system? Who didn't drool over those lenses in the Contax case while holding a 28-105 Canikon/Minolta zoom that most enthusiasts were using at the time? Where did that go? You guys know what i mean, don't you?
wayne seltzer wrote:
Sounds plausible but I think you maybe dreaming a little for the new ZE/ZF 25 to be f1.4 instead of f2 which is still down from the original f2.8.
If it is f1.4, our Sony Alpha bretheren will be very upset.
Of course FM'er Toothwalker knows but he can't tell us.
Come on, Paul. You can tell me. Send me an e-mail and I promise not to tell anyone else. I'll buy you a beer the next time I'm Belgium (or Norway, or wherever you happen to be). :-p
e_dawg wrote:
Basically, i expect more when i hear the name Zeiss. Where is that legendary Zeiss superiority... the IQ that was in a different league compared to the Canikon and Minolta fare of the film era? Remember the Contax G2 system? Who didn't drool over those lenses in the Contax case while holding a 28-105 Canikon/Minolta zoom that most enthusiasts were using at the time? Where did that go? You guys know what i mean, don't you?
Which is why I suspect the ZA lenses are more Sony/Minolta designs then Zeiss designs with licensing paid to Zeiss just for their stamp of approval/branding...but I have no evidence.
I really don't think Minolta had much to do with the ZA primes at all. Back when the 85 and 135 ZA were announced, most speculated that Sony had the basic designs ready before they acquired the A-mount, probably for their own potential DSLR mount. I would call both of those primes exceptional performers. As for the zooms, who knows? Zeiss had never been known as a fast zoom maker, and it's tough to say how those designs came about. Regardless, Zeiss certainly claims at least SOME responsibility for the ZAs.
