Bridges Loc: Memphis, Charleston SC, now Nazareth PA

The storied z8 has finally come about and has everything we hoped it would but here is a question: How much difference does the stacked sensor make? I currently have a z7ii with the mpx. being the same as the z8 am wondering if upgrading would be worth it. Yes, the eye detection is better on the z8 with it being able to detect birds, and even airplanes vs. the 7 which only detects people, dogs, and cats. I do so little with birds, the eye detection alone is not worth the difference. So many of the great reviews really hit on the video capability of this camera and my video usage is 0 (zero). It looks like it has the best video capabilities of the big three with only Panasonic being a competitor in that area but again, I don't care about video. If a stacked sensor is a considerable improvement on the sensor in the z7ii, it will definitely be a factor in whether to upgrade or not. I was hoping the 8 would incorporate the 61 mpx. sensor Nikon has been testing to make it more competitive with Sony's 61 mpx. body. That would definitely be added to the equation. That also tells me that with them holding back on that sensor, to look for a new Nikon flagship to be in the works -- an upgraded z9 with improvements in eye detection and a 61 mpx. sensor -- call it a z1. My guess is that it would come in at around 6500.00 and would eventually eliminate the z9 from the lineup.

Canisdirus

Testing a 61MP?

Yeah...testing the Sony chip you mean.

Nikon buys off the rack from Sony...as with the Z8...Z9.

Tweaked for inputs and outputs...which Sony does for all their buyers.

The so called...'designed by' part.

You have the Z7II? Keep it...this is not much of an upgrade for you.

Bridges Loc: Memphis, Charleston SC, now Nazareth PA

Thanks for the response. And if Nikon uses Sony sensors, so what? Cross-adaptation is nothing new and has no bearing on what I see as a possibility of a new camera in the Nikon line. Back when VCRs were at their peak of popularity, there were 300 brands on the market but only 8 companies manufactured them. It would not surprise me at all if Sony didn't use some Nikon technology in their cameras as well. Mazda and Ford were making autos together and the list is endless. I would still like to know the difference in a stacked sensor vs a non-stacked one.

leftj Loc: Texas

My situation is much more simple. I would love to have the Z8 but if I sold all the cameras I have I would still be $2,000 short so for now I’ll stay put.

therwol Loc: USA

A stacked sensor eliminates the need for a mechanical shutter to prevent the "rolling shutter" effect of typical electronic shutters. It is not a feature that improves IQ, just a feature that allows you to take pictures of fast moving objects with an electronic shutter without rolling shutter distortion.

In my opinion, and I say this without having used a 61 megapixel sensor, 45 megapixels is already at the point of diminishing returns in terms of capturing detail. When I was using a D810 with a 36 megapixel sensor, I already felt that the sensor challenged some of my lenses, and when I went to the D850 with 45 megapixels, the amount of detail captured was barely more and only with my best lenses. Would the Z lenses have made a difference? I don't know, and I'm not going to spend the money to find out.

User ID

That is 90% NOT true. A BSI sensor reads out faster so it somewhat reduces rolling shutter, but doesnt eliminate it.

The micro wiring grid is placed behind the sensels rather that running between them on the front side. That allows space for larger sensels, usually worth not quite one full stop of noise avoidance.

The marketing jargon "Stacked Sensor" is just as non specific and meaningless as "Mirrorless Camera".

BTW, @OP: 61MP offerrs about 25% more resolution than 45MP. Very important to peepers, otherwise not a big deal.

larryepage Loc: North Texas area

The difference between the BSI (Back Side Illuminated) sensor of the D850 and the Z7/II and the stacked sensor of the Z9 and Z8 is in both the design and the manufacturing process used to make them. Both are two-layer integrated circuits with a sensor on one layer and logic and processing circuitry on the other layer.

For the BSI device, the sensor level is made first. A logic/processing layer is then built on top of that, and as a final step, the bottom surface is ground off to expose the sensor elements. The whole thing is then installed "upside down" so that the light of the image can strike the elements of the sensor. But even with this improvement, the photodiodes had to share space with their "pixel transistors," limiting their size and thus their ability to capture light.

For the stacked device, the photodiodes and their associated transistors are made on two different wafers, which are then bonded (wired) together. The photodiode array can occupy the entire surface of the sensor, substantially increasing its ability to capture photons. These combined layers are then connected to a third logic/processing layer. It seems to me that the whole backside grinding operation is eliminated in the process, although that is not absolutely clear from what Sony has published. They obviously have to keep the best of the secrets for their competitive advantage.

Thank you for asking this question and prompting me to research the difference. There are brief mentions in the marketing materials and specifications of some pretty remarkable low light capabilities for the Z8 (like focusing to EV -9 with a f/1.2 lens in something called Starlight Mode). My immediate interest in the Z8 had cooled a little. This new look has sort of rekindled it a little bit. I'm going to have to look a little deeper.

Bridges Loc: Memphis, Charleston SC, now Nazareth PA

A not-so-important feature that also appeals to me is the deeper grip. I have very long fingers and the grip would be an advantage. So far, the two improvements that I would like to have but can live without are the eye detection improvement and the grip. The most notable improvements seem to be in the video area which I do not care for at all. Having been enthused to grab a z8, I now think it can wait for a year until they begin hitting the referb section in the Nikon store.

larryepage Loc: North Texas area

There's an error in my first paragraph. The BSI sensor is a two-layer integrated circuit. The Stacked Sensor has three layers, as described correctly a couple of paragraphs later.

gwilliams6

Stacked sensor BSI are the fastest reading sensors short of a true global shutter sensor.

Those that think it makes no difference have obviously never used a stacked sensor. Stacked sensors are the reasons those cameras can have insanely fast frames per second shooting, and with that much faster readout they have the best Tracking and AF performance.

Also fast reading stacked sensors greatly reduce the rolling shutter effect in electronic silent shutter when video shooting , and in electronic silent shutter in still shooting of fast moving subjects.

All huge benefits, and now the latest stacked sensors can also do flash sync in electronic silent shutter shooting, an industry first. NO other digital cameras sensors, BSI or not, can do flash sync in electronic silent shutter shooting.

Know the facts, and know why stacked BSI sensors are in the "flagship" fullframe mirrorless cameras from Sony (A1) , Nikon (Z9) and Canon (R3) , and in some cameras of smaller sensor sizes also.

Stacked sensors now exceed BSI CMOS sensors in focus speed, accuracy, and subject recognition. This all works together to ensure that stacked cameras don't just take a bunch of photos in a row; they take a bunch of in-focus photos in a row.

Another advantage that was made possible by the stacked sensor is the 'no blackout' or 'blackout free' EVFs.

You should look at this for a thorough explanation with illustrations.
"Why Stacked Sensor is the Future of the Camera Industry?"
https://techinspection.net/stacked-sensor-is-future-of-camera-industry/#:~:text=A%20standard%20CMOS%20sensor%20has,CMOS%20sensor%20contains%20multiple%20layers.

Know the facts ,and dont listen to folks here who commented and who obviously dont know the facts, LOL

I personally have owned two fullframe mirrorless cameras with stacked sensors, the 24mp Sony A9, and now the 50mp Sony A1. I reach for my stacked sensor A1 when I need all its stacked sensor advantages. I also have two fullframe cameras without stacked sensors, the 61mp Sony A7RIV, and the video-centric 12mp Sony A7SIII.

Cheers and best to you.

(Download)

therwol Loc: USA

I stand somewhat corrected, but let me say that for all PRACTICAL purposes, the BSI sensor can be a substitute for a mechanical shutter in reducing rolling shutter/focal plane distortion. How it is done doesn't really matter, and that's why the cameras using this technology don't need a mechanical shutter. As for 45 versus 61 megapixels, you're going to need some damn fine lenses to see a difference in detail. When do you get to the point where no full frame lenses can honestly resolve the detail that a sensor can provide? I don't know the answer, but I see so little difference between 36 and 45 that I think we've been there for a while.

larryepage Loc: North Texas area

One correction...stacked sensors are not back side illuminated. Whereas BSI sensors were built monolithically, the stacked sensors are constructed of three separate layers bonded together vertically. The big breakthrough was figuring out how to handle 1,000 C bonding temperatures vs. the more traditional 400C temperatures. But the benefit is not having to grind silicon substrate off of a photodiode built upside down on the wafer

Architect1776 Loc: In my mind

A good review of the Z8.
Cheaper and lighter Z9.
https://www.youtube.com/watch?v=Ux3Z8piSl3k

User ID

But is the end result really that much different than a BSI sensor ? Seems to me like a production engineering break through rather than any innovation for the user.

larryepage Loc: North Texas area

In another discussion I said that very thing. In fact, according to Photons to Photos, the two sensors are identicak in performance above ISO 400. For some reason, the older BSI sensor is a little better (dynamic range) below that.

Ive been trying to learn if it is easier to stack and bond three layers (it's done at the wafer level) or grind off the back of the two layer version. I'd think eliminating the grinding operation would be a good thing.

The benefit Sony claims is that the photodiode sites are larger on the newer sensor. That does sound like a plus...certainly in the context of UHH lore.