The most obvious difference is vignetting light fall off and optical vignetting (oval shape bokeh)
Is there any other such good comparison studies done? esp for the 85mm f1.2? I would like to know I am getting "something" for the extra size and weight.
Given the short backfocus of MILC the large apertyure mount is not absolutely necessary like it was with the old Canon 50/1 or 85/1.2 EF SLR lenses.
However, a larger diameter mount is stronger and more rugged. That's reason enough for me. The old F mount was often a problem over time on the larger lenses. The Sony FE mount is just OK, but subpar my Canon RF (or even the old EF) and Z.
My understanding is that it is particularly good for wide angle lenses when the rear element can be close to the sensor. I’m not a lens designer though, so what do I know?
I also remember seeing it touted that the design of the mount let lenses be smaller, and I’m a little dismayed that Nikon hasn’t pursued that much with its lens range. Perhaps the new 70-200/2.8, etc., are signs that they’re reconsidering their design priorities.
If I am not mistaken it helps in the design of wide angles and ultra fast lenses (f/1.2 or faster). I do not know if it also provides a benefit to IBIS, probably but not sure.
wind30 wrote:
I have both sony and nikon systems and I have always wondered if the larger size of nikon lens has any advantages and if so where.
The events that have taken place since the first Nikon Z cameras were introduced to the market suggest that the reason Nikon decided to make a wider mount that is closer to the sensor is to enable all lenses—including Sony lenses—to be adapted to Z cameras, having adopted a protectionist policy of not granting licenses to third-party manufacturers to produce native Z-mount lenses.
Canon has adopted an even worst protectionist policy.
panos.v wrote:
If I am not mistaken it helps in the design of wide angles and ultra fast lenses (f/1.2 or faster). I do not know if it also provides a benefit to IBIS, probably but not sure.
I recall (I think) that one of the 1001 Nights entries mentioned enlarging the mount for the Z system. The obvious geometric reason is that it accommodates a larger rear element. A mount too small effectively becomes an aperture that blocks light from the sides of the rear element from reaching that side of the sensor. The 1001 Nights article didn't describe it quite that way but did mention the viewing angle. A new mount could also let the lens sit closer to the sensor because it did not have to allow room for a mirror to swing out of the way. There wasn't just one reason. A redesigned and larger mount was the end result.
shinyobject wrote:
My understanding is that it is particularly good for wide angle lenses when the rear element can be close to the sensor. I’m not a lens designer though, so what do I know?
I also remember seeing it touted that the design of the mount let lenses be smaller, and I’m a little dismayed that Nikon hasn’t pursued that much with its lens range. Perhaps the new 70-200/2.8, etc., are signs that they’re reconsidering their design priorities.
But you don't need that wide of a mount to have the lens close to the sensor. Leica had rangefinders nearly a century ago.
not just the mount size but also the lens size. Nikon obviously has chosen to go the big lens route. A lot of new lenses are touting being the lightest ever. I am wondering what are the tradeoffs.
p.1 #10z mount larger size... how does it help IQ?
A lot of key Z lenses are much lighter than their F-mount versions. e.g. the f/2.8 zooms (14-24, 24-70 and 70-200 f/2.8). The 14-30/4 and 24-70/4 are also very compact.
wind30 wrote:
not just the mount size but also the lens size. Nikon obviously has chosen to go the big lens route. A lot of new lenses are touting being the lightest ever. I am wondering what are the tradeoffs.
p.1 #11z mount larger size... how does it help IQ?
In some of the designer interviews they talk about the F mount dimensions over time becoming constraining to what the designers could do.
They have freedom to approach optical problems in different ways. I think in general Nikon has tried to fix more optical problems in the glass rather than rely on software corrections. This has led to the lenses being larger. They also have a focus on creating good bokeh transitions. To do this they need to avoid excessive clipping of the edges which leads to a wider path and larger glass.
Also on lenses like their f1.2 line they clearly decided to go all out on optical “perfection” and size was secondary. There is no magical free lunch in lens design. To get small you have to accept more optical aberrations. Nikon is at its heart an optical company which influences their choices.
p.1 #12z mount larger size... how does it help IQ?
ilkka_nissila wrote:
A lot of key Z lenses are much lighter than their F-mount versions. e.g. the f/2.8 zooms (14-24, 24-70 and 70-200 f/2.8). The 14-30/4 and 24-70/4 are also very compact.
We should compare apples to apples, i.e., Sony FE and Nikkor Z lenses.
Several FE-mount lenses are lighter and/or more compact than those with a Z mount, even though the Z mount is wider and closer to the sensor. OP asked if and how this could help IQ.
OP then cited the 35/1.2 and the 85/1.2 as examples. As for the former, both the Viltrox and the Sigma are smaller and lighter. He provided a link to BastianK’s comparative review, which concludes:
"The Nikon Z 35mm 1.2 S Nikkor is a well-balanced lens in terms of optical performance, as there isn’t any particular flaw I could point out here. Price and dimensions are a different story, though: since it is by far the most expensive and, at the same time, the largest and heaviest lens in this comparison, it should excel in most categories, but only its vignetting figures are slightly lower and its flare resistance marginally better compared to the Viltrox.”
About 14-30/4 S, let me remind its size (89x85 mm) and weigth (485 g). It's compact and lightweight for sure, nevertheless, the Canon RF 14-35/4 IS is slightly heavier (540 g) and bulkier (84x100 mm) however it has more range and built-in image stabilization. Moreover, it has a much more comfortable 77 mm filter thread (like the Z 24-70/2.8 S II ...). Therefore, the Canon can be considered just as compact and lightweight as the Nikon when we take into account its additional features.
About the 24-70/4 S, no equivalent lens with F-mount was made by Nikon. Canon made the EF 24-70/4 IS that had a similar size and weight (and IS, which requires a dedicated optical group that adds weight and size).
Ultimately, the world's largest mount and the shortest flange focal distance among all full-frame mirrorless systems currently in production do not seem to offer significant advantages in terms of size, weight, or image quality. It allows adapting FE-mount lenses for sure.
Last but not least, let me remind that Leica M mount is neither as wide nor as close to the sensor, and yet the lenses for the Leica M aren't that bad ...
p.1 #13z mount larger size... how does it help IQ?
I am not sure why nikon does not do more lens like Plena. The difference in the plena is very obvious vs the other 135mm f1.8. I have owned sony 135mm f1.8 and canon 135mm f1.8 and the difference if the bokeh is pretty obvious. The nikon version managed to improve that without being heavier or bigger which is kind of amazing.
The 35mm f1.2 has very nice bokeh in the transition zone and was one of the reasons why I bought into nikon. However, the competition has since caught up with pretty good offerings from both Viltrox and Sigma.
I also got the nikon 85mm f1.2 which is HUGE. After testing, it is good but I don't see anything special about it...
p.1 #14z mount larger size... how does it help IQ?
wind30 wrote:
I am not sure why nikon does not do more lens like Plena.
I think the existence of Plena is the answer to your question. Its image circle is much bigger than the competition, which gives you less vignetting and higher resolution in the corners. A wider mount helps. Why not do more lenses like that? I think they do. The f/1.2S primes come to mind, but they aren't everyday lenses due to bulk.
And if we look at slower and lighter lenses, I very much enjoy the 28mm f/2.8 and 40mm f/2 Nikkors. Sony doesn't offer exact equivalents. But in the same weight class they have the 24mm f/2.8, and the 40mm f/2.5. Both vignette more at the same apertures than the Nikkors. Again, we can't know for sure, but the wider mount could have helped.