Variability of Sony/Zeiss lenses

[rodeo_joe1]

I recently bought, and quickly returned, a used 'Zeiss' E-mount 24-70 f/4 vario-Tessar. 

I was swayed by the high(ped?) reputation of Zeiss lenses and was expecting great things, but the sample I got was pretty damn poor. Despite the mechanical condition of the lens only showing light use, its central definition wide open was so poor that the focus-peaking of the camera barely lit up, and consequently the camera AF with the lens was unreliable.

With hindsight I should have done my homework first, but it seems that there's a big variability among reviews of this lens, and a recognised quite high probability of getting a 'wrong un'. 

So, why do these made in Thailand lenses continue to command a high price? Because surely a big part of a lens maker's reputation is in having good Q. C. and keeping bad copies off the market? If they can't do that, then you might as well take a risk with the likes of Samyang and keep hold of a big chunk of change if you stay lucky. 

In fact my satisfaction with Samyang lenses is very high, but I recognise that their percentage of 'dogs' or 'lemons' is perceptably higher than the God-like Zeiss brand name. 

Do we have a fallen giant and a god that's lost their powers?

Edited January 8, 2023 by rodeo_joe1

[Ken Katz]

I have found that the reviews done by these folks match up well to equipment I have used:

https://www.photozone.de/sonyalphaff/867-zeiss2470f4oss

They were not fans of that lens either,  and the sample they tested had good centering qualities.

[rodeo_joe1]

Thanks Ken. That was one of the reviews I looked at - after purchase and brief testing! 

None of the reviews was downright damming. I guess they have to tread carefully if supported by advertising sponsorship. But phrases like 'have reservations' or 'slight concerns' should ring alarm bells I now realise. 

Anyway, lesson learned. Do the homework and look before you leap, etc. 

That said; there was no way I was expecting such poor image quality from a lens with the Zeiss badge on it. Did Zeiss even have a hand in its design, I wonder? Or just accept payment for use of the name? 

[Ed_Ingold]

The Sony/Zeiss 24-70/4 is not highly regarded. It's okay as a kit lens, but the distortion and sharpness leave much to be desired. The Sony/Zeiss 16-35/4, which I also own, is a good performer. I don't feel a need to bump up to the f/2.8 GM version, since it's my least used zoom lens. If I feel the need to go wide, I prefer prime lenses.

[Mark Keefer]

Thanks for the post. Good to know.  

[Colin O]

Sony did a few things to get a good foothold in the digital camera market. First was to join with (Konica)Minolta on the A mount, and before they'd even released a camera, Sony went the next step and bought (almost) all of Minolta's photo assets. That gave them a load of existing users who had lenses waiting for a camera, or new users who liked the idea of a huge availability of lenses on the used market.

Next thing Sony did was start releasing "Zeiss" lenses for their system - before they were established as a respected player in the digital camera market themselves. But there isn't really anything much Zeiss about these lenses. They are certainly not made by Zeiss. The designs were done by Sony, according to online chatter, and they were manufactured by Sony. The well-known Zeiss trademarks like Sonnar, Tesser, Planar, etc that you might see on these lenses, they really have very little to do with the actual lens formulas of the Sony Zeiss lenses; these lenses are modern many-element autofocus lenses. I guess the lenses do use Zeiss T* coating, but come on, anyone who thinks Zeiss has some unassailable lead on its competitors just by virtue of their coating, they are fooling themselves. There's also been online talk that the Sony Zeiss lenses were subjected to "Zeiss quality control"... which again really should be taken with a large grain of salt - it's such a tenuous link to the tradition of quality optics that Zeiss earned itself many years ago.

If you watch Sony's recent and new lens releases, none of them come with the Zeiss branding anymore - I think the most recent Sony Zeiss lens was introduced in 2016. That's because Sony has by now established itself as one of the major players in the digital camera industry, with high-quality lenses in its own right. Sony doesn't need Zeiss to sell lenses anymore - their own G Master lenses have a reputation for almost technical perfection. Sony Zeiss was just marketing and a little blue badge. Not very different really to Nokia putting the Zeiss name on their cameraphones.

Edit: I just realised I'm replying to a thread started over a year ago - oops. Not much activity in this forum.

Edited February 19 by Colin O

[Colin O]

Little bit more info which I guess will be interesting for (future) readers...

Zeiss made an official blog post about their Sony partnership - at http://blogs.zeiss.com/photo/en/?p=6131 - which is no longer accessible, though can still be accessed through the Internet Archive.

Most interesting/relevant parts...
 

Quote

Who develops the lenses?

ZEISS lenses are developed exclusively by ZEISS. ZEISS also determines the features of the lenses, such as their focal length and internal construction, in line with the company’s product strategy.

Sony/ZEISS lenses are jointly developed by ZEISS and Sony. ZEISS supports Sony throughout the optical design and development process and then tests and approves the prototypes. Finally, ZEISS determines the test specifications for serial production.

 

Quote

Where are the lenses manufactured?

ZEISS still picture lenses are manufactured in Japan and ZEISS cine lenses in ZEISS’s factory in Oberkochen/Germany. It is still economical for ZEISS to produce its cine lenses in Germany due to the more sophisticated skills required to manufacture these special lenses for the film industry. In order to satisfy the much higher global demand for still picture lenses, ZEISS has established a partner network in the optics industry. During the entire development and production processes, ZEISS experts ensure that the high quality standards for which ZEISS has been famous for over 165 years are met.

Sony/ZEISS lenses are manufactured by Sony in factories across Asia. In these factories Sony uses lens testing equipment that has been developed and manufactured by ZEISS. An example is the MTF-tester K8, a versatile and compact instrument used to measure the modulation transfer function of photographic lenses, or similar systems, at an infinite object distance.

 

Quote

Is the quality of both lines identical?

In all its brand partnerships, ZEISS sets the technical and quality standards to which partners, such as Sony, must adhere. ZEISS regularly audits the production process of Sony/ZEISS lenses in Sony’s factories. ZEISS experts examine the production processes, management systems and measuring installations. ZEISS certifies the suppliers and provides all the equipment that is needed to ensure product quality, including the equipment of third-party suppliers.

 

Edited February 20 by Colin O

[rodeo_joe1]

To slightly redeem my experience with the shoddy Vario-Tessar: I've since acquired a Sony-Zeiss 55mm f/1.8 ZA Sonnar and a Zeiss 25mm f/2 Batis, used and in VG condition. They're both optically excellent and aquit themselves extremely well on the 60 Mpx a7riv, even in the extreme corners of the frame and wide open. Auto focus is fast, accurate and near-silent. 

However, I did reject one sample of used 55mm ZA Sonnar I was offered, due to centre-frame smearing that was obvious even in a magnified viewfinder image. Damaged by a former owner? Who knows. 

All I can say is; if you get a good 'un, the 25mm Batis or 55mm Sonnar are very, very good. But then that could apply to quite a few lenses. 

[Colin O]

Might be of interest, but I believe that the Batis lens formulas were matched by online sleuths to patents published by Tamron. Not that there's really anything wrong with that, but it's interesting to be aware that Zeiss, again, puts its name on modern photography lenses without really developing/manufacturing them in the way that people might imagine.