Below is a conversation I had with Zeiss about the performance of their lenses for DSLRs. Zeiss' replies are in bold.
I would hope you might review this report comparing Zeiss lenses with Nikon and other lenses in terms of performance:
DxOMark - Nikon D800 and standard lens choices
I have a good working relationship with Carl Zeiss MicroImaging (through my profession) and yet see again and again in reports on these ZF lenses that they perform poorly in comparison to Nikon optics. I love the lens designs but if they cannot perform even a little bit better optically than a Nikon lens, I cannot justify spending money on them for my digital cameras.
Zeiss:
Thank you for your inquiry to Carl Zeiss and your interest in our products. Which aspects of a lens´performance you are mainly interested in?
Which lenses (focal lengths) exactly are you interested in?Like every product, all lenses or lens types have their advantages and disadvantages. It is impossible to condense all aspects of the performance of a lens in just one number like DXO does.Those typical chart tests just do a comparison of a few aspects of different lenses in a reproduction application on a test chart. Their performance, handling, durability, precision and behaviour in typical practical applications are never taken into account. So the performance at infinity and with typical 3-dimensional objects, their rendering of out-of-focus details (bokeh), the preciseness of the focusing and many other aspects relevant for typical applications are not represented by this "DXO Mark Score".
Other reviewers base their verdicts on lenses on really practical applications. Especially Lloyd Chambers and Sean Reid do a lot of practical tests with all of our SLR lenses, resulting in much more realistic test results.
diglloyd - Guide to Zeiss ZF/ZE Lenses
Reid Reviews
(access to the tests has to be payed for)
Photozone offers a mix of lab tests and practical tests of our lenses:
All Tests / Reviews
Our current SLR lenses are well-balanced regarding the different aspects of their performance.
Among our current SLR lenses (ZE and ZF.2 types), there are a few classical lens types (e.g. Planar T* 1,4/50, Planar T* 1,4/85) and some very high performing new designs (e.g. Distagon T* 2,8/15, Distagon T* 2,8/21, Makro-Planar T* 2/100 and the new Apo Sonnar T* 2/135), which outclass the comparable lenses from other manufactures in practical photography and all serious tests by far.
If you need further details about some specific lenses out of our current product line, please do not hesitate to contact us.
Thank-you for taking the time to reply, I appreciate it, and thank-you for the links. I had been interested in the 50 mm 1.4 Planar but opted based on reviews I had seen with the Nikon 50 mm 1.4 G. I am presently considering the Nikon 85 mm 1.4G as it performs the best in the DxoMark tests, but would consider a Zeiss 85 mm 1.4 Planar. I would be using the lenses with a Nikon D800 (full frame) and Nikon D7000 (APS-C) for still photography primarily (wedding and industrial) and occasionally video. I am also considering the Nikon 24 mm 1.4G and am curious how it would compare with the Zeiss 21 2.8. The 135 f/2 apo from Zeiss would be interesting as well to compares against the Nikon 135 f2 DC.
I'm looking for quantitative measures of performance, specifically MTF (which I know is on the Zeiss website) and lp/mm. But also how MTF relates to aperture, vignetting, image distortion and degree of chromatic aberations.
Zeiss:
MTF at two different aperture values, vignetting at different aperture values, and distorsion values also can be found in the data sheets on our website. Distorsion of a lens is not depending on the aperture value, just depending on the image ratio.
It does not make sense to publish the maximum resolution of a lens - in practical use, always the resolution of the camera/sensor and limitations regarding accurate focusing etc. limit the resolution of a resulting picture.
Many aspects about the performance of our lenses are mentioned in the tests from Lloyd Chambers and Sean Reid.
It seems that you approach lenses exclusively from the technical data. We strongly recommend to test and compare lenses in real life situations, which gives you a much more detailed overview about them.
Please take the chance to test our lenses at your Carl Zeiss photo dealer or rent them to have the chance for an intensive test.
You can find your nearest Carl Zeiss Photo Dealer in our dealer search:
Photography
Hoping to be of service to you we kindly ask you to contact us again should you need further assistance.
Thank-you for the information and I will certainly check out the reviews you mentioned. I agree with you that real-life images provide the most information as to performance. I do often look for examples online of photos taken with the respective Zeiss lenses and of course they look great. I am usually very impressed with the color rendition of Zeiss lenses. I suppose I ask myself how far can we push the resolution of the lens to take advantage of the high resolution sensors and do the Zeiss optics achieve that. Zeiss optics are no doubts superb in many respects but of course to go with manual focus on a DSLR, there has to be a very good reason to put aside the AF Nikon lenses and good reasons would be simply significantly better sharpness and contrast in the images with negligible distortion and negligible flaring/coma/fringing. Then there is the question of whether the Zeiss lenses made in Japan are as good as previous lenses made in Germany.
Zeiss:
Well, of course, Nikon also provides some very interesting lenses. Depending on the desired lens type and the application, it is really a question if AF or MF would be the better choice.
For all "non-mobile" objects, a manual focus lens with a long rotating angle and a smooth focusing ring will allow more precise focusing. For shapshots, sports, reportage, wildlife etc, an AF lens could be the better choice, irrespective of the optical performance.
In our globalized world, it does not play much of a role anymore where a product is assembled. All of our lenses, irrespective of the country where they are manufactured, are produced according to the same specifications, measured on the same measuring machines (K8 MTF tester) like here in Germany.
In our current product portfolio of SLR lenses, we have some outstanding lens types, and a few classical lens types, giving a special vintage look when used wide open.
I would hope you might review this report comparing Zeiss lenses with Nikon and other lenses in terms of performance:
DxOMark - Nikon D800 and standard lens choices
I have a good working relationship with Carl Zeiss MicroImaging (through my profession) and yet see again and again in reports on these ZF lenses that they perform poorly in comparison to Nikon optics. I love the lens designs but if they cannot perform even a little bit better optically than a Nikon lens, I cannot justify spending money on them for my digital cameras.
Zeiss:
Thank you for your inquiry to Carl Zeiss and your interest in our products. Which aspects of a lens´performance you are mainly interested in?
Which lenses (focal lengths) exactly are you interested in?Like every product, all lenses or lens types have their advantages and disadvantages. It is impossible to condense all aspects of the performance of a lens in just one number like DXO does.Those typical chart tests just do a comparison of a few aspects of different lenses in a reproduction application on a test chart. Their performance, handling, durability, precision and behaviour in typical practical applications are never taken into account. So the performance at infinity and with typical 3-dimensional objects, their rendering of out-of-focus details (bokeh), the preciseness of the focusing and many other aspects relevant for typical applications are not represented by this "DXO Mark Score".
Other reviewers base their verdicts on lenses on really practical applications. Especially Lloyd Chambers and Sean Reid do a lot of practical tests with all of our SLR lenses, resulting in much more realistic test results.
diglloyd - Guide to Zeiss ZF/ZE Lenses
Reid Reviews
(access to the tests has to be payed for)
Photozone offers a mix of lab tests and practical tests of our lenses:
All Tests / Reviews
Our current SLR lenses are well-balanced regarding the different aspects of their performance.
Among our current SLR lenses (ZE and ZF.2 types), there are a few classical lens types (e.g. Planar T* 1,4/50, Planar T* 1,4/85) and some very high performing new designs (e.g. Distagon T* 2,8/15, Distagon T* 2,8/21, Makro-Planar T* 2/100 and the new Apo Sonnar T* 2/135), which outclass the comparable lenses from other manufactures in practical photography and all serious tests by far.
If you need further details about some specific lenses out of our current product line, please do not hesitate to contact us.
Thank-you for taking the time to reply, I appreciate it, and thank-you for the links. I had been interested in the 50 mm 1.4 Planar but opted based on reviews I had seen with the Nikon 50 mm 1.4 G. I am presently considering the Nikon 85 mm 1.4G as it performs the best in the DxoMark tests, but would consider a Zeiss 85 mm 1.4 Planar. I would be using the lenses with a Nikon D800 (full frame) and Nikon D7000 (APS-C) for still photography primarily (wedding and industrial) and occasionally video. I am also considering the Nikon 24 mm 1.4G and am curious how it would compare with the Zeiss 21 2.8. The 135 f/2 apo from Zeiss would be interesting as well to compares against the Nikon 135 f2 DC.
I'm looking for quantitative measures of performance, specifically MTF (which I know is on the Zeiss website) and lp/mm. But also how MTF relates to aperture, vignetting, image distortion and degree of chromatic aberations.
Zeiss:
MTF at two different aperture values, vignetting at different aperture values, and distorsion values also can be found in the data sheets on our website. Distorsion of a lens is not depending on the aperture value, just depending on the image ratio.
It does not make sense to publish the maximum resolution of a lens - in practical use, always the resolution of the camera/sensor and limitations regarding accurate focusing etc. limit the resolution of a resulting picture.
Many aspects about the performance of our lenses are mentioned in the tests from Lloyd Chambers and Sean Reid.
It seems that you approach lenses exclusively from the technical data. We strongly recommend to test and compare lenses in real life situations, which gives you a much more detailed overview about them.
Please take the chance to test our lenses at your Carl Zeiss photo dealer or rent them to have the chance for an intensive test.
You can find your nearest Carl Zeiss Photo Dealer in our dealer search:
Photography
Hoping to be of service to you we kindly ask you to contact us again should you need further assistance.
Thank-you for the information and I will certainly check out the reviews you mentioned. I agree with you that real-life images provide the most information as to performance. I do often look for examples online of photos taken with the respective Zeiss lenses and of course they look great. I am usually very impressed with the color rendition of Zeiss lenses. I suppose I ask myself how far can we push the resolution of the lens to take advantage of the high resolution sensors and do the Zeiss optics achieve that. Zeiss optics are no doubts superb in many respects but of course to go with manual focus on a DSLR, there has to be a very good reason to put aside the AF Nikon lenses and good reasons would be simply significantly better sharpness and contrast in the images with negligible distortion and negligible flaring/coma/fringing. Then there is the question of whether the Zeiss lenses made in Japan are as good as previous lenses made in Germany.
Zeiss:
Well, of course, Nikon also provides some very interesting lenses. Depending on the desired lens type and the application, it is really a question if AF or MF would be the better choice.
For all "non-mobile" objects, a manual focus lens with a long rotating angle and a smooth focusing ring will allow more precise focusing. For shapshots, sports, reportage, wildlife etc, an AF lens could be the better choice, irrespective of the optical performance.
In our globalized world, it does not play much of a role anymore where a product is assembled. All of our lenses, irrespective of the country where they are manufactured, are produced according to the same specifications, measured on the same measuring machines (K8 MTF tester) like here in Germany.
In our current product portfolio of SLR lenses, we have some outstanding lens types, and a few classical lens types, giving a special vintage look when used wide open.