Sony Zeiss 35mm FE vs Soon to be available Loxia 35mm

[JohnAONeill]

Hi folks

I'm not an MTF chart expert by any means so I'm hoping to hear thoughts from others who know better than I do on this topic. Based on the design/specs on the new Zeiss Loxia 35mm for FE mount is this really worth the wait or is the Zony 35mm really that good? For street shooting on the A7 is manual focus fast enough? I like fast glass and the Sony just seems to fall a little short for me. I've only seen two sample images posted on the loxia which look nice (does anyone know where I might find some larger sample images?). Or better yet has anyone reviewed these yet?

Regards
John

[ErikKaffehr]

Hi,

Regarding AF I guess that if you need AF, Loxia would not be a consideration. Do you have time to focus accurately, using magnified live view, it may be another game.

The Loxia lenses are based on the Zeiss ZM designs, but they need to be adjusted to sensor characteristics.

Personally, I judge lenses pretty much on MTF curves. Zeiss published measured MTF for their lenses, but Sony curves are either calculated or designed by the marketing department. They cannot be compared.

I looked at the 50 mm lens, and it looks to be good, stopped down.

Personally, I would be most interested in Loxia lenses if Sony made a decent A series camera, something like this:

• First Electronic Curtain
• Larger battery
• OLP filter
• Around 50 MP
• On sensor phase detecting AF

The combo would be:

Ultra wide zoom, but probably Sigma 12-24 for Alpha mount
Normal zoom, 24-105/4 if available
Tele zoom, 70-400/4-5.6 for Alpha mount

Loxia lenses 24, 50, 85 if available.

For me the question is hypothetic, right now, as I don't feel the A7 offerings are exiting enough. I am happy with my Sony Alpha 99 and my MFD kit offers 39 MP when I need it.

Best regards
Erik

Hi folks

I'm not an MTF chart expert by any means so I'm hoping to hear thoughts from others who know better than I do on this topic. Based on the design/specs on the new Zeiss Loxia 35mm for FE mount is this really worth the wait or is the Zony 35mm really that good? For street shooting on the A7 is manual focus fast enough? I like fast glass and the Sony just seems to fall a little short for me. I've only seen two sample images posted on the loxia which look nice (does anyone know where I might find some larger sample images?). Or better yet has anyone reviewed these yet?

Regards
John

[Paul Roark]

I am going to wait for real world tests.  The Zony 35 2.8 is a very good lens.  The ZM Biogon 35 f/2 was considered a very good lens for film, but the ZM had the usual smear on the corners of the Sony according to internet reports.  The Loxia appears to be a rather minor modification of the ZM Biogon.  The Loxia corner performance on the Zeiss published MTF is no very encouraging.

Frankly, for the Sony sensor I think the older design is not going to be able to compete with the modern designs that have digital in mind.  The compact versions of the Biogon 35 and 21 ZMs were favorite M9 optics.  I hope the new Loxia can pull it off, but I'm skeptical.

Paul
www.PaulRoark.com

[ErikKaffehr]

Hi,

That smearing is coming mostly from astigmatism caused by the optical package in front of the sensor (about 2 mm thick). Hopefully the optical construction has been modified to handle that.

Next question if outlet pupil distance is to short?

I am not intending to be first buyer, but I would sort of expect that if Zeiss redesigns a series of lenses for a special camera that those lenses would work well on that camera.

Best regards
Erik

I am going to wait for real world tests.  The Zony 35 2.8 is a very good lens.  The ZM Biogon 35 f/2 was considered a very good lens for film, but the ZM had the usual smear on the corners of the Sony according to internet reports.  The Loxia appears to be a rather minor modification of the ZM Biogon.  The Loxia corner performance on the Zeiss published MTF is no very encouraging.

Frankly, for the Sony sensor I think the older design is not going to be able to compete with the modern designs that have digital in mind.  The compact versions of the Biogon 35 and 21 ZMs were favorite M9 optics.  I hope the new Loxia can pull it off, but I'm skeptical.

Paul
www.PaulRoark.com

[ErikKaffehr]

Hi,

It seems that the Loxia 35 mm works much better on the Sony than the Biogon:

http://3d-kraft.com/index.php?option=com_content&view=article&id=168:zeiss-loxia-2-35-short-comparison-review&catid=40:camerasandlenses&Itemid=2

Best regards
Erik

[rainer_v]

i think/hope  that they wil change the thickness of their sensor glass, but if they do that they wont construct lenses specifically for this a7r spec, which seems to be the result of a design error..

[ErikKaffehr]

Hi,

Sony A7 sensor glass is about 2 mm, which is pretty much standard in the industry, Leica (0.8 mm) and 4/3 (4 mm) are the exceptions.

Zeiss did redesign the Loxia lenses for the Sony sensor.

These samples are from Loxia 35/2 and  Biogon 35/2 on A7r  (source: http://3d-kraft.com/index.php?option=com_content&view=article&id=168:zeiss-loxia-2-35-short-comparison-review&catid=40:camerasandlenses&Itemid=2) :


Best regards
Erik

i think/hope  that they wil change the thickness of their sensor glass, but if they do that they wont construct lenses specifically for this a7r spec, which seems to be the result of a design error..

[robdickinson]

Bad or terrible.


Skip these I think.

[Telecaster]

Bad or terrible.

Skip these I think.

Geez, the examples were shot wide open with a 36mp sensor and are shown at full res. (Also note, as Erik has mentioned, that the ZM version is poorly suited to a camera with a relatively thick filter stack in front of the sensor.) In the real world who's gonna take such a photo and expect tack sharpness across the entire frame? Of course Zeiss can provide something close to that (Otus line) but it comes with a huge size & cost penalty. These lenses are compact and far more affordable.

Personally I'll stick with the Sony/Zeiss 35 & 55mm AF lenses. But I'd consider the Loxias if I were using an A7s with an emphasis on shooting video.

-Dave-

[ErikKaffehr]

Hi,

Most wide angles are quite terrible in the corners fully open, so I guess the Loxia actually does a very good job.

I am not really in for A7x, but I may be interested in next generation, if they improve sensor, like Electronic First Curtain and PDAF on chip, and make a resolution bump.

I essentially like manual focus, at fully magnified live view, so I would be interested in medium speed manual focus lenses.

I am pretty sure that Otuses and Sigma Art's are superior, but I guess they are a bit heavy, and neither fits the Sony EF without an adapter.

Best regards
Erik

Geez, the examples were shot wide open with a 36mp sensor and are shown at full res. (Also note, as Erik has mentioned, that the ZM version is poorly suited to a camera with a relatively thick filter stack in front of the sensor.) In the real world who's gonna take such a photo and expect tack sharpness across the entire frame? Of course Zeiss can provide something close to that (Otus line) but it comes with a huge size & cost penalty. These lenses are compact and far more affordable.

Personally I'll stick with the Sony/Zeiss 35 & 55mm AF lenses. But I'd consider the Loxias if I were using an A7s with an emphasis on shooting video.

-Dave-