Z mount advantage over F mount: wide angle only?

[q.g._de_bakker]

It (post or in-camera corrections) is only possible when you have enough resolution.

Down- and up sampling to correct geometic errors. Bayer patterns and the artefacts they produce. All except correcting vignetting are artefacts in themselves, replace content where real-world information should have been.

[Rob Davies]

Oooo! You mean it can't be switched off?

 

This review..

 

Nikon Nikkor Z 14-30 mm f/4 S review - Distortion - LensTip.com

 

measured the distortion without correction by using a 'dumb' RAW converter.

 

I use LR /ACR, should probably have mentioned that. :)

[ilkka_nissila]

Quite common these days I'm afraid. Why would anyone care where the very good optical performance comes from and how it is achieved? Isn't the result what counts?

 

Yes, but if very large corrections have to be applied, it can show negatively in the outcome. Correcting strong vignetting can result in uneven luminance and uneven color, increases noise in the corrected areas which can lead to a visibly lower quality image. Correcting strong distortion can result in uneven sharpness and often only a partial correction is achieved. I generally prefer lenses that have moderate or low distortion and vignetting.

 

However, e.g., the 14-30/4 Z is a really compact lens for something of its size and focal length range and thus it adds value to the user by the hybrid approach to corrections. I have seen very impressive results from this lens (high contrast, vivid colors even when the sun is in the frame, which I don't believe I have ever seen in such an ultrawide angle lens). A large number of elements which would be needed to correct distortion more optically would probably mean a larger, heavier, more expensive lens which might suffer more from flare and ghosting. If the approach chosen in the 14-30/4 does not suit your purposes, there is also the 14-24/2.8.

 

Of course, mount such a lens on a camera body that doesn't apply those corrections, and things get a tad difficult. I doubt that the post-processing corrections that some software can apply is as good as what the manufacturer included in-camera.

 

If you shoot raw, the camera doesn't apply distortion correction to the image data but provides a set of instructions / parameters on how to do it in the raw correction software. But in my experience Nikon make a compromise between correcting the distortion fully and losing a lot of resolution in parts of the frame. You can adjust the correction to some extent in post. In my experience, DXO's software provide the most accurate distortion correction profiles, not the camera manufacturer. DXO even measure the distortion at different subject camera distances and use the distance information in the file to choose the most accurate correction.

[Gary Naka]

From my perspective, it gave Nikon the chance to "clean slate" their lens to camera connection, and design a LONG TERM solution.

 

While the F mount has stayed the same since the 1960s, the method of communicating between the lens and camera has been changing; pre-AI, AI, AF, AF-S, AF-P, G, E, etc. making true backwards compatibility impossible.

Those of you with different generations of Nikon F mount lenses and cameras know what I mean.

When I bought my D7200, I did so specifically because it had an AF motor in the body, to autofocus the mechanical AF lenses that I had. The D3xxx and D5xxx do not have an AF motor in the body, so cannot autofocus the mechanical AF lenses.

When I plan to buy a F mount lens, I have to check the compatibility chart, to make sure that the lens will work on my camera, because not all will. This is something that the consumer really should not have to do.

The Canon guys are snickering at us.

[ilkka_nissila]

Backwards compatibility is not impossible, however, it is likely inconvenient for the engineers to always have to consider that, and as a result, the least expensive camera models make some compromises (no AF motor, no Ai metering). All my current DSLR cameras work with all the F-mount lenses I ever used in my adult life (as a child I had access to three pre-Ai Nikkors and those would have to be modified to work on my current cameras, but it is a mechanical modification that should still be possible). If you get a Canon lens from the 1970s or early 1980s there is no modification which will make it work (without focal length change and with infinity focus) on Canon DSLRs. Canon have since the EF mount maintained good compatibility. However, now they make cameras for four different mounts (EF, M, RF, and PL). That's quite a lot of adapting to do to manage into the future. Neither company has a perfect record, Canon made a more abrupt bump (complete incompatibility between their MF and AF systems) in the 1980s while Nikon have made a series of smaller changes which lead to less disruption at each point but of course it lead to a very complex system over the course of 70 years. Nikon have not maintained the compatibility of old cameras with new lenses, but with mid and higher-end cameras (including all FX DSLRs) the support of old lenses is there.

 

Nikon have pushed through a few updates which necessitated that I upgrade body earlier than I would otherwise would have wanted; the first was the introduction of VR which was not compatible with all earlier camera bodies but required newer bodies to operate, so I replaced my F90X with the F100 to get access to the VR of the 70-200/2.8. Another case was when Nikon finally put in radio triggers in 2016, and this meant I would replace the D810 with the D850 to get access to it. In practice probably most use non-Nikon radio triggering methods that work with a broad range of flashes (at least some do).

From my perspective, it gave Nikon the chance to "clean slate" their lens to camera connection, and design a LONG TERM solution.

 

To some extent, yes, but it takes very long to design and put into production a complete lens system let alone get the users to move into that. In practice Nikon have to design their Z cameras with some F system compatibility in mind.

[mike_halliwell]

From the measurements in the review (above) vignetting reaches -3.5EVs at the wide end wide open. That's a lot of brightening that will inevitably increase noise substantially. Say you took it at ISO 800. The outer edges/corners are now ~ISO 8000....:eek:

 

At 14 mm FX you get barrel distortion of −7.04%. How you can 'correct' that in post without smearing is a marvel in itself!

[Dieter Schaefer]

At 14 mm FX you get barrel distortion of −7.04%.

The lens performance according to lenstip's review reminds me a lot of that of the Nikon AF-S 16-35/4 (Nikon Nikkor AF-S 16-35 mm f/4G ED VR review - Distortion - LensTip.com). Sky-high distortion at the shortest focal length (-6.33%), marked performance decrease towards the longer focal length (the test results, though done on different cameras, D3X vs Z7, and hence values aren't directly comparable) show a remarkable close resemblance in their overall shape.

[ilkka_nissila]

The lens performance according to lenstip's review reminds me a lot of that of the Nikon AF-S 16-35/4 (Nikon Nikkor AF-S 16-35 mm f/4G ED VR review - Distortion - LensTip.com). Sky-high distortion at the shortest focal length (-6.33%), marked performance decrease towards the longer focal length (the test results, though done on different cameras, D3X vs Z7, and hence values aren't directly comparable) show a remarkable close resemblance in their overall shape.

 

The 14-30 is much sharper than the 16-35 according to imatest measurements

 

Nikon Z 14-30mm f/4 S Review - Page 4 of 7 - Photography Life

 

Though the site noted some sample variation. :/ I am wondering if a full distortion correction would move the areas that have this blurriness outside of the resulting slightly cropped image area.

Edited February 3, 2021 by ilkka_nissila

[Dieter Schaefer]

The 14-30 is much sharper than the 16-35 according to imatest measurements

Thanks Ilkka, I had forgotten about the test comparison on photographylife.com. I'm not surprised at the differences in sharpness; after all, that's the kind of performance promised for the superior lens designs possible for the Z-mount and reduced flange-to-sensor distance. In comparison with the 16-35, the Tamron 15-30/2.8 performs better; the latter also holds is own against the Nikon 14-24/2.8 (with the Tamron stronger at wider apertures). Frankly, I had hoped for a more even performance across the frame from the Z-mount lens - which it does deliver at f/8 across all focal lengths, making it the preferred choice for landscape photography by far. There's not too much light between the F-mount lenses mentioned here at that aperture.

[daniel_bliss]

Strangely, Sony with its narrow-throat E-mount doesn't seem to inhibit the release of optically excellent lenses. Makes me wonder if Nikon's Z-mount really had to be that big and whether at least some of the lenses as a result are larger than necessary. On the other hand, Nikon's 14-30/4S and 14-24/2.8S appear to be lenses that could not have been done for the F-mount and possibly can't be done for Sony E-mount either.

 

 

I believe Sigma has demonstrated that higher performing lenses are also possible for the F-mount (looking at the 40/1.4 Art as one example) but that the resulting lenses are excessively large and heavy. And it appears that somewhat smaller and lighter lenses are possible for the wide-throat Z-mount - though none of the lenses currently available can claim to be compact. The popular 14-24/24-70/70-200 f/2.8 set was already fairly expensive in its latest F-mount manifestation; the current Z-mount trio ups the prices once again.

 

Wish I'd seen this sooner, but not just Sigma -- have you seen Tamron's 35mm f1.4 for Nikon and Canon DSLR? It's clearly the best-in-class lens right now, DSLR or mirrorless--what an outcome for being Tamron's first ever f1.4.

[mike_halliwell]

Tamron's 35mm f1.4 for Nikon and Canon DSLR? It's clearly the best-in-class lens right now, DSLR or mirrorless--what an outcome for being Tamron's first ever f1.4.

Depending on your strict definition of 'Class', the Sigma 40mm 1.4 is clearly better.... but yes, it's not a 35mm lens.

 

5mm difference isn't much....;)