Nikon’s new mirrorless system, coming in ... late September 2018

[BernardLanguillier]

An interesting article about focus fine tuning on the Z7.

https://blog.reikanfocal.com/2018/10/the-new-nikon-z7-investigating-with-reikan-focal/

Cheers,
Bernard

[armand]

An interesting article about focus fine tuning on the Z7.

https://blog.reikanfocal.com/2018/10/the-new-nikon-z7-investigating-with-reikan-focal/

Cheers,
Bernard

Why does it need to? Isn't the focus achieved on the sensor? Is there focus shift when the aperture is closed?

[BernardLanguillier]

Why does it need to? Isn't the focus achieved on the sensor? Is there focus shift when the aperture is closed?

All that is explained in the article.

Cheers,
Bernard

[davidgp]

All that is explained in the article.

Cheers,
Bernard

Umm... reading the article seems to imply that Nikon does not do at the end of the PDAF adjustement a CDAF tuning like Other mirrorless cameras do...

I always thought that was the case (with the exception of Canon that always said they were not doing in their dual pixel technology)



http://dgpfotografia.com

[BernardLanguillier]

Umm... reading the article seems to imply that Nikon does not do at the end of the PDAF adjustement a CDAF tuning like Other mirrorless cameras do...

I always thought that was the case (with the exception of Canon that always said they were not doing in their dual pixel technology)

Indeed but considering the need to adapt AF-S lenses with good level of AF performance, it does make sense that they went for a solution where contrast AF isn't needed.

But this is just a plausible guess at this point. I don't think anybody got an official explanation from Nikon regarding the way the Z AF works.

AF-C and AF-S may not be working the same way either. AF fine tune is common to both AF-S and AF-C, so we don't really know how it works for both modes.

Cheers,
Bernard

[Rory]

I was really keen on focus stacking - in fact, it was one of my reasons for getting the Z7. Unfortunately, the user interface for focus stacking is ... awkward. The most annoying thing about it is that the live view goes away while you're setting it up, and there's no way to actually aim the camera before starting the sequence. This makes handheld focus stacks almost impossible (although I tried). This isn't because I don't believe in tripods - I do, and like to use them where possible. But a lot of my shooting is in the backcountry, where every gram counts. I can easily handhold well enough to do half a dozen shots at different focus distances, which is enough depth of field even for the very large canvas prints I make, if combined with stitching. I tried attaching this function to a control ... but I still get taken to the focus stack screen, and so I can't see what I'm trying to focus stack. Too bad - this would be such a simple firmware fix. More sensible control over the focus increments would be really handy too, and would also be easy to calculate in camera (if Nikon folks were interested, I'd be happy to help them out).

Anyway, hope this of value to someone...

For a small system focus stacking you should try the Olympus EM1 (version 1 or 2).  With the outstanding image stabilization and live view of stacking in real time it is easy to use and works very well handheld.

[davidgp]

Indeed but considering the need to adapt AF-S lenses with good level of AF performance, it does make sense that they went for a solution where contrast AF isn't needed.

But this is just a plausible guess at this point. I don't think anybody got an official explanation from Nikon regarding the way the Z AF works.

AF-C and AF-S may not be working the same way either. AF fine tune is common to both AF-S and AF-C, so we don't really know how it works for both modes.

Cheers,
Bernard

I suppose one way to know some info is when people starts to reverse engineer to make adapters or third party lenses but I doubt that even them we will know for sure...

[Telecaster]

My main motivation for mostly dumping AF SLRs was their "guesstimate and hope" PDAF implementations. No AF system is perfect but for me CDAF has been way more consistently accurate than any PDAF system I've used. I'm also fine with hybrid PD/CD AF systems…but a PDAF-only mirrorless system would be a non-starter.

-Dave-

[SrMi]

My main motivation for mostly dumping AF SLRs was their "guesstimate and hope" PDAF implementations. No AF system is perfect but for me CDAF has been way more consistently accurate than any PDAF system I've used. I'm also fine with hybrid PD/CD AF systems…but a PDAF-only mirrorless system would be a non-starter.

-Dave-

People are reporting that the pinpoint AF mode is CDAF. Some believe that there is a CDAF trim step in other modes. I do not know of any reliable source that provides the necessary information.

[Guillermo Luijk]

It is not ideal, I really wanted a D850 sensor in that Z7 body. Interestingly at ISO 100 is less obvious that at ISO 64 but there it's behind the A7R iii.

Surprised to see such evident stripes. I don't know how much underexposed was the shot, but it doesn't seem a too demanding scene. The point is that you get stripes where you still have detail.



Regards

[BernardLanguillier]

PDAF on mirrorless eliminates most of the cause of errors found in DSLR, which the subtle positioning of AF sensors. It pretty much only leaves the lens side aspects.

Contrast AF is inherently an iterative, and therefore slower, process that is a poor match for subject tracking.

Designing a PDAF that has to be good enough to focus accurately without contrast AF is IMHO the best way to get real mid to long term improvements.

I don’t mind doing fine tuning of my lenses.

Cheers,
Bernard

[BernardLanguillier]

Surprised to see such evident stripes. I don't know how much underexposed was the shot, but it doesn't seem a too demanding scene. The point is that you get stripes where you still have detail.

That doesn’t look good.

On the other hand, I tried to brighten a daylight scene at ISO64 4 stops in LR and wasn’t able to generate any banding, even in the darkest part of the scene.

Cheers,
Bernard

[vjbelle]

I too am alarmed by this report.  Maybe you can try a little harder to replicate what DPR seemed to uncover.  Maybe a typical scene where there is strong sunlight which causes under exposure to eliminate clipping and see what happens when raising shadows...... I'm sure you have but maybe one more try. To me, if this is substantiated, this would be cause to eliminate this camera.  I'm used to bringing up shadows with my 3100 and GFX at will with no banding.

Victor

[gkroeger]

Now I understand why I was unable to make any good images for 40 years with reversal film.  I could never underexpose by 5 stops and then print the area as neutral gray. Better start ripping the prints off the wall.

[SrMi]

Lots of people are trying to reproduce the banding that DPR is reporting, to no avail.
I tried underexposing an indoor scene by 5 stops, lifting it by 5 stops in Lightroom and cannot see any banding at ISO 64. Once I start destroying the image (shadows +80) the banding starts appearing. I.e., it exists, but it is unclear in which cases they are visible in useful images.

[SrMi]

Surprised to see such evident stripes. I don't know how much underexposed was the shot, but it doesn't seem a too demanding scene. The point is that you get stripes where you still have detail.



Regards

Where did you get that image from? This looks like an overprocessed image of the image (JPG) published on DPR.

[gkroeger]

That is not the original jpeg published by DRP... it has the contrast jacked way up bordering on posterization.

[armand]

Why don't you wait a bit, rent the camera to check it out...
I am sure there are some things that could be better since its their first FF ML.
For one the sensor needs a very short read-out-time  to make it more useful; am not sure were these new ML's stands and there will be tests and reviews all over the place.
I have a d850 and that serves me well...  although i see the benefit of ML in some cases.
 (and still have the lightweight nikon1 that i really like and can combine with all my nikkors)

Well, too late. Having the D850 experience for the first time I preordered a camera but it became available much sooner than I expected.
I tried to cancel it but it was too late. I'm debating if I should send it back without opening or to give it a shot. On a side not I forgot I need a XQD card so if I want to keep it I need to buy one of those too, I see cheap is not one of their qualities.

[jeremyrh]

Not a big fan, but Tony Northrup has a comaprison of image quality on his YouTube channel where he tests Z7 vs D850 vs A7r3 vs EOS R.  The bottom line is - they're all about the same, banding and all (not the D850).

Back to taking photographs ....

[davidgp]

This sound all too familiar... the banding issue I mean... now everybody is saying is the doom of everything... others saying it is not a problem... in a few weeks you will have people enjoying the camera, Jim Kasson put this in better words than me: https://blog.kasson.com/nikon-z6-7/z7-silly-season/

In resume, Z7 sensor is a tiny bit worst because of the PDAF system on top of some photodiodes than the D850 sensor? Of course it is!!! Matters too much? I suppose if you bought the camera just for pure sensor performance and you already have a D850... yes, then it matters... for the rest, enjoy the camera...


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