Does changing Picture Control Sharpness improve AutoFocus accuracy with Mirrorless bodies in low light?

[TonyBrown]

OK, just did some informal testing. I'm in my room in Costa Rica (we have the morning off) and have a tile wall (lots of texture) in our shower that makes a nice target. With the bathroom lights off, I can go along the wall and it gradually goes from where the camera can't focus to where it can. I set Shooting Bank A for the default Auto picture control, set bank B the way Thom describes, and then bank C for Vivid (I don't use the banks and just made copies of bank A before I started, so all other settings - and exposure settings - are the same). As I go along the wall with each, they all grab focus at the exact same spot, no difference. I would think if added sharpening (and contrast in the case of Vivid) were helping the AF system, I'd see those options grab on just before the Auto picture setting (since the wall is the same all over - the only difference is brightness) and that's not the case.

Again, it's informal but I wanted to share. If I run into a real world situation where the camera struggles, I'll switch to bank B or C and see if things improve and report back.

I am currently waiting for my Z9 and am debating whether to keep my D850 and D6 when I get it. Obviously, I will do my own field testing when it arrives, but am wondering Steve whether your Z9 has become your ‘go to’ camera?

 

[Steve]

I am currently waiting for my Z9 and am debating whether to keep my D850 and D6 when I get it. Obviously, I will do my own field testing when it arrives, but am wondering Steve whether your Z9 has become your ‘go to’ camera?

The a1 is still my go-to, but it depends on my mood most days LOL. I honesty don't care which camera I'm using that much, I can make either one work. The a1 controls and customization are simply a better match for my needs and it's still sticker with BIF.

 

[NorthernFocus]

The a1 is still my go-to, but it depends on my mood most days LOL. I honesty don't care which camera I'm using that much, I can make either one work. The a1 controls and customization are simply a better match for my needs and it's still sticker with BIF.

Steve, you're so diplomatic. I got tired of all of the bickering and rhetoric so got the A1 a couple of months ago to try out for myself. I've shot Nikon my whole photographic career and the A1 solves virtually every complaint I've got with the various Nikon bodies. And particularly with the Z9. Unfortunately it's not just about the camera and there are still a lot more choices for lenses with Nikon. So now I'm stuck with both. But if I'm just grabbing a camera for a quick shoot it's the A1 every time now. It's just easier. I can concentrate on the subject and not on operating the equipment. Now if I could just find a Sony 600 f4 laying around somewhere unattended ...

 

[Bob Hullinger]

It's clear the processors, sensor and evf are closely integrated in the designs of these high performance Mirrorless cameras.
Socionext upgraded its fab processing last year for custom CPUs, which may well have helped to improve the EXPEED7 performance, including heat its management.

https://bcgforums.com/index.php?threads/z9-rumored-specs-are-out.9744/post-98840

Everything companies like Socionet, other chip makers also, produce is "custom". I've never heard of generic chipsets. I agree those components are very closely integrated given that the device wouldn't function without them.

 

[Bob Hullinger]

The a1 is still my go-to, but it depends on my mood most days LOL. I honesty don't care which camera I'm using that much, I can make either one work. The a1 controls and customization are simply a better match for my needs and it's still sticker with BIF.

I hate those jerks at Sony. I think they are out to take advantage of me They never design cameras with Nikon lens mounts so all my lenses will work on them. Life just isn't fair.

 

[Robert Weller]

This thread is getting a bit old by now, but I hadn't seen it before Steve's weekly heads-up email, and I think that it might be useful to expand just a bit on Thom's point. All the Nikon literature says that the histogram is not created from the raw image, but from a JPEG, and many of us use the histogram to set exposure, so the question is what histogram does Nikon use? Do they create a special, for-the-histogram, JPEG, or is it THE JPEG associated with the image, which presumably has been processed using the Picture Control settings? I would be really surprised if the camera expends the compute cycles to make a second JPEG just for the purpose of building the histogram. That is too extravagant computationally to imagine, particularly when most cameras are so starved for computing power. I've been suspicious for quite some time, going back to my Z7 that the exposure that I choose to make is being subtly influenced by the Picture Control settings. This is quite different from the settings influencing the RAW image. They don't do that, but do they influence the photographer? And as critically, does the Picture Control setting also influence the way that the camera itself decides to expose the image? I have not set up a controlled experiment to test this, but as in Thom's point about the autofocus, if the Z cameras use the JPEG that is created for display, which is controlled by the Picture Control settings, in order to focus and set exposure, however that is done, shutter speed, aperture or (auto) ISO, then the question is not whether the Picture Control settings affect the camera's automatic functions, but whether the effects are observable in images, whether by the camera's own decision, or those of the photographer.

 

[John Navitsky]

I've been suspicious for quite some time, going back to my Z7 that the exposure that I choose to make is being subtly influenced by the Picture Control settings.

keep in mind, the metering computations on the mirrorless cameras differs a bit than the dslrs. iirc the mirrorless cameras can better take the *subject* into consideration with metering. there was a pretty dramatic example here lately where someone had the setting to prioritize faces enabled and the image was exposed for the face even though the face was in shadow using matrix metering

 

[bleirer]

This thread is getting a bit old by now, but I hadn't seen it before Steve's weekly heads-up email, and I think that it might be useful to expand just a bit on Thom's point. All the Nikon literature says that the histogram is not created from the raw image, but from a JPEG, and many of us use the histogram to set exposure, so the question is what histogram does Nikon use? Do they create a special, for-the-histogram, JPEG, or is it THE JPEG associated with the image, which presumably has been processed using the Picture Control settings? I would be really surprised if the camera expends the compute cycles to make a second JPEG just for the purpose of building the histogram. That is too extravagant computationally to imagine, particularly when most cameras are so starved for computing power. I've been suspicious for quite some time, going back to my Z7 that the exposure that I choose to make is being subtly influenced by the Picture Control settings. This is quite different from the settings influencing the RAW image. They don't do that, but do they influence the photographer? And as critically, does the Picture Control setting also influence the way that the camera itself decides to expose the image? I have not set up a controlled experiment to test this, but as in Thom's point about the autofocus, if the Z cameras use the JPEG that is created for display, which is controlled by the Picture Control settings, in order to focus and set exposure, however that is done, shutter speed, aperture or (auto) ISO, then the question is not whether the Picture Control settings affect the camera's automatic functions, but whether the effects are observable in images, whether by the camera's own decision, or those of the photographer.

Though the only possible source for the jpeg is the raw data from the sensor. There is no other. Even a jpeg only shooter would have a raw file first but discarded after the jpeg is created from that raw. I think the unique thing about the z9 is the dual stream of the data from the sensor, not just for raw file creation but for other uses as has been discussed.

 

[RAWky]

I found an interview with Fujifilm, where it is explained how PDAF works on mirrorless cameras and the need of special PDAF-pixels between RGB-picture-pixels.

You'll find it in the middle of the interview:

Is Fuji’s AF the most advanced out there? Plus their coming 100-megapixel body. Fujifilm Q&A from CP+!

I had a chance to sit down with two top Fujifilm execs (Toshihisa Iida and Makoto Oishi) at the recent CP+ 2019 show in Yokohama, Japan, to ask them about everything from the state of the industry to my usual tech-geeky questions…

www.imaging-resource.com

Think about: To get a phase (a curve of photo-motif-contrast), you need not only one (1) ZA/ZB-pixel-pair, you need a lot of them.

 

[fcotterill]

Thanks for sharing, as I'd missed that IR interview somehow. What a pity Dave Etchells is no longer with IR. He published some fascinating articles on several of these Japanese companies.
This PDAF and sensor physics gets technically complex fast. Much to digest....

 

[nautiboy]

This doesn't answer your question about picture controls, but if you want to improve low-light AF and you're willing to give up the WYSIWYG display you can try turning on starlight mode. Previously I had really only used it with actual night time shots, and only considered it for that application. But then I accidentally forgot to disable it and was taking some post-sunset shots and noticed that it was doing a better job focusing. I've used it a few times since in low-light scenarios, and while it's a little bit of a bummer not to have the WYSIWYG display, I found it easier to see and easier to focus.