I realize manufacturers think they're getting free publicity with these 'leaks' on rumor sites leading to 'pre announcements' and then a white paper or marketing leaflet and a few test shots and so on, but MHO is that they'd be better off releasing all of the facts on the marketplace en masse so people can make informed decisions/comments rather than weeks of speculation based on the bits and pieces that are available which inevitably leads to as many people being turned off as would be drawn into the crowd.
I just think there are far too many unknown variables at play to really judge the lens by those particular shots. We are all expecting the Biogon on the A7/A7r to underperform but I'll wait for real proof that Zeiss really screwed this up.
Not looking too promising for me - I would use them for landscape-type shots and the corner blurring is also disappointing. Hopefully someone that knows how to shoot with these lenses on the A7r will get them in their hands and give them a true workout and evaluation.
For those prices I would expect very good wide open performance and excellent across the frame stopped down a bit.
jhinkey wrote:
Not looking too promising for me - I would use them for landscape-type shots and the corner blurring is also disappointing. Hopefully someone that knows how to shoot with these lenses on the A7r will get them in their hands and give them a true workout and evaluation.
For those prices I would expect very good wide open performance and excellent across the frame stopped down a bit.
It's a good job this new Zeiss lens has autofocus.
owls have both highly evolved hearing and eyesight for hunting at night. they don't use sonar like bats so they need their eyes to fly at high speed in near darkness through forests. they have giant eyes (similar in size to ours in much smaller heads) that can open the iris extremely wide (large aperture), reflective tissue at the back of the retina like cats so that any light that is not absorbed by the photo receptors is reflected back towards them, and a much higher ratio of rods to cones than we do for better sensitivity in low light. the lower number of cones means that they sacrifice color sensitivity for low light performance (just like canon), not sure how that last bit relates to the otus.
mogul wrote:
Since it has stopped down metering, I wonder if you focus wide open and stop down, will we get a focus shift?
My guess is that any focus shift won't be too bad as these lenses are only f/2 and not f/1./4, and the ZM versions don't have bad focus shift either. We will have to wait until someone gets them to know for sure, however.
All words below were written by Carl Zeiss themselves in response to questions about their Loxia line of lenses (excerpted from various websites on the web):
"Our Loxia lenses have ten aperture blades and aperture is almost circular."
"Loxia lenses are designed for manual focus. The design as a manual focus lens allowed us to work with much lower tolerances in volume production during the mechanical design phase. The user feels this precision every time he uses the lenses. Furthermore, we wanted to provide users with the freedom to use the focus position as an artistic tool because this is one of the most important creative instruments available to photographers. We are therefore delivering an extra fine feel and a precise focusing mechanism that can be achieved in a model featuring a lens with manual focus in an all-metal housing. This makes the lenses in the new family particularly suitable for all areas of application in which personalized, manual photography flexes its muscles, e.g. portrait, travel and landscape photography. The integration of an autofocus motor always means making compromises with the mechanical precision of the lens design. With precise manual focusing, it is also possible to use the lenses for video applications in the semi-professional area."
"Here definitely will be additional focal lengths in the Loxia family of lenses. However, at this point we cannot go into details. We expect to introduce another focal length by mid-2015."
"The high-quality lens shade for the Loxia lenses is made of metal."
"The focus rotation is 180 degrees."
"The Biogon T* 2/35 ZM and Planar T* 2/50 ZM are based on decades of proven optical designs whose roots stretch far back in the history of ZEISS. They combine good value for the money, small size, robustness and a long service life."
"The Loxia 2/35 and Loxia 2/50 build on these proven designs and are adapted for use on modern digital mirrorless full-frame system cameras. As well as the possibility of camera-internal image optimization, the Loxia 2/35 and Loxia 2/50 feature a far shorter minimum object distance than the Biogon T* 2/35 ZM and Planar T* 2/50 ZM: 0.3 m compared to 0.7 m for the Loxia 2/35 and 0.45 m compared to 0.7 m for the Loxia 2/50."
"The starting point of the optical design has been well known optical constructions. These have been tuned to fit perfectly the Sony sensor. This means that the optimization has been done taking into account the effect of the glass plate in front of the sensor."
"The Loxia 2/50 is a complete different lens than the Sonnar T* FE 1.8/55. It is more optimized for smoothness than for contrast at high aperture."
"It is 100% mechanical and as such is mechanically linked to the blades. The aperture is the same while composing than when shooting, like on traditional lenses."
"For the manufacture of ZEISS lenses, we use a global production network of trusted partners in the optical industry that has been built up over many years. Loxia lenses are made in Japan."
"The MTF charts for ZM lenses base on K8 measurements based on the conditions that can be found in (analogue or digital) M-mount cameras (e.g. no glass plate, or extremely thin glass in front of the sensor), whereas Loxia lenses are measured according to the typical conditions in E-mount full-frame camera bodies (e.g. thick glass plates in front of the sensor). So naturally, different results are typical."
"The Loxia lenses are full-frame lenses for mirrorless system cameras. Sony is currently the only manufacturer offering mirrorless system cameras with full-frame sensor – the Alpha 7/ 7R/ 7S. Loxia lenses with X-mount are technically possible, but nothing is planned yet."
Why Zeiss Chose 35mm and 50mm Focal Lengths to start (photographicwanderings.com):
"The goal with the new Loxia family was to develop a new lens line that can be used for both still photography and for video. We will not compete with the existing Sony/Zeiss branded AF lenses for the FE mount, since they are already well received for still photography. However, there are limitations to using an AF lens when focus pulling and in this regard, the Loxia lenses will provide better control. We’ve incorporated a manual iris on the lens (which is unique to E mount lenses) and the user has the option of ‘de-clicking’ the f/stop detents to allow for continuous aperture control.
We started with the 2/35 and 2/50 first, since these are the most popular focal lengths for video. The 35mm focal length is also the most popular among rangefinder shooters – especially street shooters, who we will target with this new lens line as well. Zone focusing will be a snap when using the focus and DOF scales on the lens – also unique to E mount lenses.
Of course, there are customers who will adapt their M mount lenses to use with the A7 series, but these do not offer any direct communication with the camera and have to be used 100% manually. The price of the Loxia lenses (which includes a lens shade) is less than the cost of a M mount lens + adapter + shade. So there is both convenience and a cost savings to the customer.
We’ll add to the family in the future with wide-angles and short telephotos. The challenge with these mirrorless cameras is designing an ultra wide angle lens that does not exhibit vignetting, lens shading and the ‘smearing’ effect common when using adapted wide-angle M mount lenses.”
Feel free to add comments that they made which I missed!
rishio media wrote:
"The MTF charts for ZM lenses base on K8 measurements based on the conditions that can be found in (analogue or digital) M-mount cameras (e.g. no glass plate, or extremely thin glass in front of the sensor), whereas Loxia lenses are measured according to the typical conditions in E-mount full-frame camera bodies (e.g. thick glass plates in front of the sensor). So naturally, different results are typical."
So the MTF's for the Loxia lenses already account for the thick glass plate in their measurement. That's great news with regard to the Biogon in particular.
Steve Spencer wrote:
My guess is that any focus shift won't be too bad as these lenses are only f/2 and not f/1./4, and the ZM versions don't have bad focus shift either. We will have to wait until someone gets them to know for sure, however.
Both ZM have minimal but detectable focus shift. The 50 is really excellent in this regards. The 35 is slightly worse. At MFD, the focus will shift by around 2cm between f/2 and 4. The lens is designed to front focus wide open so it's easy to compensate and most of the time the shift goes unnoticed. It's not evident in the online samples if the Loxia 35 has similar SA characteristics.
Tariq Gibran wrote:
So the MTF's for the Loxia lenses already account for the thick glass plate in their measurement. That's great news with regard to the Biogon in particular.
Great news indeed. I also like that the planar has been designed with smoother bokeh in mind than the Sonnar 55. This said, the ZM planar really has great bokeh too, despite the common misconception that it is harsh, probably confused with the G45.
Jman13 wrote:
I'm starting to think that the 18mm flange focal distance and full frame don't play nicely together.
Perhaps, but I'm also thinking it's a matter of them choosing to lightly modify the ZM35. Had they started from scratch, I'm sure better could have been possible. But at what price?
I also agree with the comment about companies not providing full documentation with these kinds of releases. What's the thinking behind posting 1/2 or 1/3 resolution images wiped of EXIF? It just drives the speculation further. It comes across as either incompetent or of something to hide.
Is it far fetched to think that as sensor technology improves and is better able to handle oblique light angles, these lenses would become better with time? I'd imagine it shouldn't be too far away where they can get rid of the glass in front of the sensor and use things such as organic sensor layers (though I don't really know what I'm talking about!)
edwardkaraa wrote:
Great news indeed. I also like that the planar has been designed with smoother bokeh in mind than the Sonnar 55. This said, the ZM planar really has great bokeh too, despite the common misconception that it is harsh, probably confused with the G45.
rishio media wrote:
Is it far fetched to think that as sensor technology improves and is better able to handle oblique light angles, these lenses would become better with time? I'd imagine it shouldn't be too far away where they can get rid of the glass in front of the sensor and use things such as organic sensor layers (though I don't really know what I'm talking about!)
I hope you're right.
Really, I've been thinking for years that instead of concentrating their resources and time to develop new lens designs to accommodate the current ( and finicky ) sensor technology, manufacturers should focus (pun intended.) on developing a sensor which behaves like film concerning angles of incidence. No need to get a new specific line of glass for each series of cameras with different sensor stacks. That's a waste of time and money. Go direct to the point Mr.Sony and give us a film-like sensor without any crappy glass on top.
Of course, the devil's advocate inside me thinks also that they (Sony, Fuji, Zeiss, Olympus..) are happy with the current situation. People can't use properly their legacy lenses with the A7x or the Fuji-X cameras. They need to buy native glass or new 'dedicated' Zeiss manual offerings for the more demanding customers. More lenses to sell More profit. Don't be surprised if the new 'revolutionary' mirrorless from any of the big names sports a 5 mmtr.thick sensor stack.
artur5 wrote:
Go direct to the point Mr.Sony and give us a film-like sensor without any crappy glass on top.
Sony may already have the technology (at least they have patents for organic sensors), but still no cost effective way to produce it.
Of course, the devil's advocate inside me thinks also that they (Sony, Fuji, Zeiss, Olympus..) are happy with the current situation. People can't use properly their legacy lenses with the A7x or the Fuji-X cameras. They need to buy native glass or new 'dedicated' Zeiss manual offerings for the more demanding customers. More lenses to sell More profit. Don't be surprised if the new 'revolutionary' mirrorless from any of the big names sports a 5 mmtr.thick sensor stack.
Seems unlikely to me that they're holding back technology because of this. The majority of photographers still want AF lenses.
