Sony announces a9 III: first full-frame global shutter camera

https://www.dpreview.com/news/7271416294/sony-announces-a9-iii-world-s-first-full-frame-global-shutter-camera

by ksec • 3 years ago

261 158 3 years ago

I love seeing global shutter on this camera. It's been amazing getting shots with cameras with global shutter for me.

Unlike film grain, the weird artifacts for sports/action, camera moves, rotary motion... it's all bad looking and disappears completely with global shutter.

buffington2• 3 years ago

Not just global shutter, but shutter speeds up to 1/80000, flash sync the same (which is simply bonkers, but possible due to global shutter), and pre-recording?

I love my A7IV, but the A9III makes it look like a toy.

semi-extrinsic• 3 years ago

FWIW, you could do shutter speeds like that on the Canon PowerShot series of cameras all the way since ~2005 due to the unofficial CHDK - Canon Hackers Development Kit.

sho• 3 years ago

While I love ridiculous specs as much as anyone, let's remember that 1/80,000th of a second is.. nuts and as far as I can find there's only one flash unit that can even do that, the profoto pro-11, which is a $20k proposition before you even buy the damn camera. And you will get very, very far from its maximum output for that kind of duration.

So it's very cool, yes, but unless you have a ton of money to spend and a very very good reason to need such extreme speed.. you're never gonna use it.

I am certainly looking at my trusty but aging a7sii with an increasingly contemptuous eye, though...

vouaobrasil5• 3 years ago

Weird artifacts and rotary motion are for all PRACTICAL purposes gone with fast, stacked shutters as in the Nikon Z9. The global shutter's main benefit is flash sync. Grain has nothing to do with global shutter....

Espressosaurus6• 3 years ago

Even with a fast readout, PWMing LEDs can still present issues for cameras like the Z9. The global shutter removes that concern entirely with no need for fine-tuning--still need some logic to identify the peak brightness but don't need to fine tune frame rates by fractions of a Hz to reduce banding.

A global shutter has been the holy grail for awhile for cameras like this in wide production. Yes, you can get a machine learning camera with 20 megapixels and a global shutter, but you'll need to strap a whole PC to it to do the data capture. And it'll be manual focus and manual aperture to boot.

zuminator• 3 years ago

Far as I can tell, OP isn't saying that grain has anything to do with global shutter, they're saying that rolling shutter produces artifacts, which unlike other photographic artifacts such as the often pleasant ones produced by film grain, are not at all aesthetically pleasing.

jillesvangurp• 3 years ago

Global shutter is a method of ending an exposure where all the image data is captured simultaneously. This is distinct from most existing shutter systems (electronic and mechanical) that start and end progressively: working their way across the sensor.

Buried at the bottom of the article. This is interesting for especially video and sports photography. Some cameras with slower sensors suffer from the rolling shutter effect where fast moving subjects get distorted because the subject or the camera is moving. Think e.g. lampposts looking diagonal when shot from a fast moving car. Capturing all the pixels in one go solves that.

Cropping the sensor is a common way to counter rolling shutter with current cameras. Basically, that means you are not using all of the pixels on the sensor and capture a smaller area. Aside from the quality, this also means that you don't use everything the lens captured; it's cropped away. So, it looks like you are using a larger focal length than you actually are and you can't capture at the full width of the lens.

Lots of cameras use cropping to support higher resolutions and frame rates because they can't read out the sensor fast enough. This new sensor can use the full resolution and doesn't have to crop.

And like with photography, you use shutter speed and aperture to control what the video looks like. 1/30th of a second is actually a relatively long exposure for a photo. And that's also potentially a lot of rolling shutter to deal with. An instant and fast readout means you have more wiggle room to play with this creatively or shoot in very bright or low light.

fullspectrumdev• 3 years ago

Thanks for the explainer - I was wondering what the significance was, and something I do is mess about with cameras for fun.

cubefox• 3 years ago

The article also mentions the downside of global shutter: lower dynamic range.

codeconscious• 3 years ago

Thank you, as I might have overlooked this downside had it not been for this comment.

The article doesn't make this immediately clear:

It's a 24.6MP camera that Sony says doesn't compromise on ISO performance or dynamic range.

Then later:

This might explain the base ISO of 250, which will ultimately limit the camera's maximum dynamic range.

Sounds like a compromise to me...

Espressosaurus6• 3 years ago

Not just the global shutter, but 120 FPS with full AF and AE is huge too. The A9III is going to be the best sports camera out there for a few years I think. Of course, you're going to pay through the nose if you want access to that tech.

I can't wait for them to gain back the dynamic range and for it to roll down to less expensive cameras in the future.

clan• 3 years ago

Agreed. Worth mentioning as well: flash sync speed. As you are not dealing with a shutter or progressive capture this will be a thing of the past.

dheera• 3 years ago

Cropping the sensor is a common way to counter rolling shutter with current camera

Not in my experience. For full-frame 35mm digital cameras, the most common way to counter electronic rolling shutter effects is, ironically, a very fast mechanical shutter.

In digital cameras with mechanical shutters, which include all Canon/Nikon/Sony/etc. consumer DSLRs and mirrorless cameras, the electronic shutter programmed to stay open for much longer than the mechanical shutter, which allows there to be a time instant when all pixels are simultaneously electronically open. The mechnical shutter then opens and closes during that time.

The rolling shutter on a Sony a7 is about 26ms. Mechanical shutters can beat that easily, and can be as fast as <0.2ms.

(Electronic shutters can be faster on a per-line basis. But they will still take 26ms to roll through the image for a rolling shutter sensor. So if your electronic shutter is set to 0.01ms you'll still be seeing 0.01ms exposures at each line but it will take 26ms to roll through the image.)

Espressosaurus6• 3 years ago

Cropping is common in video. For stills, you're correct.

mnw21cam2• 3 years ago

I don't think you're right about mechanical shutters being faster. The type of mechanical shutter on most cameras like this is a focal plane shutter[0]. It has two curtains - an upper one and a lower one. When the shutter is closed, the two overlap. For a long exposure (typically anything longer than 1/100s although some cameras are faster) the lower curtain will fall all the way, then the upper curtain will fall to close it off again. But at faster shutter speeds, the upper curtain will start falling before the lower curtain has reached the bottom, and so you can get exactly the same rolling shutter effect with a mechanical shutter as with an electronic shutter. For very fast shutter speeds, the exposure is a narrow slit between the two curtains that travels down the image at a much slower speed than the exposure time, and this is why most cameras can't synchronise with a flash at speeds faster than 1/100s or so. So therefore the type of mechanical shutter in most DSLRs and mirrorless cameras effectively have a rolling shutter transition time of 4-10ms, which is much more than the 0.2ms you claim.

Video-specific cameras are where this might be improved, because you can have a shutter which is a rotating disc, and this can allow faster opening/closing times, because it doesn't need to speed up from a standstill for each frame.

There exist central shutters which are mechanical shutters that act as a global shutter, but these are unusual because they need to be built into each lens you attach to the camera. These are typically limited to a maximum speed of 1/500s.

[0] https://en.wikipedia.org/wiki/Focal-plane_shutter

vouaobrasil5• 3 years ago

Most higher end cameras like the Panasonic G6, Nikon Z8/Z9, etc. hardly have any rolling shutter. You'll certainly NEVER see rolling shutter in any PRACTICAL application for video unless you pan like a true madman, either in photo or in video. (I am a professional photographer and videographer....)

In fact for sports and wildlife, you'll NEVER see rolling shutter in pretty much any existing camera, either in photo or video. For photography it's been like this for decades and for videography recently.

Where rolling shutter does appear is in the use of the electronic shutter only, but the Nikon Z9 already solved that, same with the Sony a1.

The main benefit is flash sync and a very SLIGHT improvement in some types of distortion when shooting at very high shutter speeds. I'd argue that the Nikon Z9 is a much better camera if not wanting flash sync due to its lower base ISO.

So to reiterate, the main benefit is not the reduction of rolling shutter, especially since any camera in this price point already has minimal rolling shutter.

Global shutters are COOL, and the reduction of rolling shutter is COOL, but not the main point, though of course most future cameras will probably switch to global shutters at some point if the base ISO can be lowered.

andrei_says_• 3 years ago

Global shutter allows for much higher flash sync speeds.

I shoot dance, often in close proximity, and rolling shutter on canon r6 was a reason enough to upgrade to r6ii.

onetimeuse923043• 3 years ago

I'd argue that the Nikon Z9 is a much better camera if not wanting flash sync due to its lower base ISO.

Yeah. I think a lot of people focus too much on those "high end" specs and too little about small, practical, quality of life things.

I remember how I instantly liked Fuji X100 for its built in ND filter. Yes, you can screw a filter on by yourself. Then you suddenly find yourself on a sunny beach and you wish you had your photo bag with you.

Not saying global shutter isn't nice feature, but that 250 base ISO can be a bit of a hassle depending on what kind of photography you do just like not everybody is going to benefit from the new shutter.

lvl1023• 3 years ago

It’s not a “very SLIGHT improvement” as you write. It’s VERY SIGNIFICANT. Even the Nikon Z9 has roughly 4ms rolling shutter speed. Light travels faster than you imply here. A lot faster.

jdietrich• 3 years ago

You'll certainly NEVER see rolling shutter in any PRACTICAL application for video unless you pan like a true madman

Fast lateral movement doesn't just happen on a whip pan. Any scene involving fast vehicles, high speed machinery or strong vibration is likely to have some level of rolling shutter artifacts. Many perfectly normal tracking shots will have some artifacts, particularly if you're shooting handheld. Modern fast-readout sensors are very good, but they aren't perfect; to a great extent, we've just got used to seeing mild rolling shutter artifacts and don't immediately recognise them as an image quality defect.

There are still lots of good reasons to use rolling readout sensors, but there are also many real advantages to global sensors.

ptsneves3• 3 years ago

Global shutter is essential for serious drone photography or photography from platforms with undamped vibrations like machinery. It means you will have discontinuities in features of the picture. You will need to re-stich the photo or post process it. For video it is just bad. An example of such pixel perfect uses was we were able to know the size of a marking on the ground with centimetre accuracy by counting the pixels.

Modern gimbals are amazing and do away with much of the issue but if you are needing pixel accurate features global shutter is the way to go.

ptsneves3• 3 years ago

An example of global shutter issues https://youtu.be/qqsDMJ7iyM0?t=86

smogcutter• 3 years ago

1/30th of a second is actually a relatively long exposure for a photo.

As an aside, in video & motion picture cameras the frame rate isn’t the exposure length. You need to account for the time the shutter is closed. So the real exposure is about 1/60, still slow but much more manageable.

vanderZwan2• 3 years ago

Some cameras with slower sensors suffer from the rolling shutter effect where fast moving subjects get distorted because the subject or the camera is moving. Think e.g. lampposts looking diagonal when shot from a fast moving car.

These days this is the least of your worries with a camera with rolling shutter. I got a Nikon Z-fc, knowing from the reviews that it would have a rolling shutter, because I don't mind these types of distortions.

What the reviews didn't mention is that many LED based lights actually alternate red, green and blue LEDs in quick succession. And you see that in photos as horizontal streaks of rapid changes in white balance. This also happens with projectors that are LED based, and CFTs if their drivers aren't fast enough.

plus• 3 years ago

Are you sure that's an artifact of the light source emitting colors sequentially, and not an artifact of the camera sensor detecting colors sequentially?

m463• 3 years ago

I hope global shutter makes its way to other brands so we can get away from the banding and jelly cam that we put up with when using digital cameras.

vouaobrasil5• 3 years ago

That stuff is already mostly gone with fast stacked shutters as in the Nikon Z9. In fact, even cheaper cameras like the Panasonic G6 don't have noticeable banding.

vr46• 3 years ago

Very cool technology, for those who don’t want, need or can’t make creative use of the visual artefacts that come with other cameras.

threeseed3• 3 years ago

Nokia has had something similar for a while now where the sensor readout was fast enough to prevent the roller shutter effect. Either way this was never a huge issue for photographers since you could always fall back to using mechanical shutters.

The more interesting part of this camera is whether this is a trend towards photography being the process of extracting a frame from a video rather than taking a series of shots.

blt• 3 years ago

How does this compare to the capabilities of DSLR with a mechanical shutter?

threeseed3• 3 years ago

So the global shutter will have no benefit today for most users.

In the future though it means we can do away with the mechanical shutter which in theory means smaller, cheaper, more reliable cameras.

However the capturing photos when you hold the focus button down feature will I think be genuinely useful for pretty much everyone. Especially in family situations with kids, pets etc.

whyenot• 3 years ago

So the global shutter will have no benefit today for most users.

It will have a benefit for anyone who is also recording video using their DSLR, likely the majority of users. It completely eliminates rolling shutter. Now, is it a benefit that is worth paying $6,000 for? That is a good question! For most users, probably not.

jiggawatts• 3 years ago

In the future though it means we can do away with the mechanical shutter

The future is a year ago: The Nikon Z9 and Z8 cameras have no mechanical shutter, and their electronic shutter speed is so fast that there is no practical issues capturing even fast motion.

SulphurCrested• 3 years ago

More capable mechanical focal plane shutters with a flash sync speed of 1/200s or faster do not show objectionable rolling shutter effects for most practical stills photography, including wildlife and most sports. Better mirrorless cameras use the same types of shutters.

Older film cameras may have had flash sync speeds of 1/60s, and rolling shutter was sometimes a problem with them.

Mirrorless cameras also have a fully electronic shutter, for silent shooting and shooting video. (Some DSLRs could also shoot video this way.) In all but a handful of very expensive cameras, it takes a long time to scan the sensor and rolling shutter is obtrusive – in many cameras it is as slow as 1/15s. In that handful of expensive cameras it is around 1/200s, like a fast mechanical shutter. Nikon’s expensive cameras don’t even have a mechanical shutter any more.

That last bit of speed, from 1/200s to the 0s of a global shutter, is detectable in certain examples Sony showed off in their presentation. Most of these examples relate to high-end sports photography.

Flash sync at any speed means flashes can be built more cheaply and cycle faster. Currently, to shoot faster than the flash sync speed the flash must emit a long burst instead of a single pulse. For this reason, some cameras used a leaf shutter, which can sync at any speed, but they were typically expensive to make and sometimes less reliable.

There are related problems to do with the refresh rate of LEDs in the field of view, which are solved by the global shutter and somewhat clumsily worked around in cameras without one by trying to sync the shutter with the refresh rate. Again, high-end sports photographers are the ones who usually encounter this problem.

xyzzy_plugh• 3 years ago

will also add C2PA authentication metadata. C2PA is a combination of the efforts of the Content Authentication Initiative and the separate Project Origin initiative.

First I have heard of this. My initial thought is "gross" but I wonder if it may actually be beneficial for the average consumer, prosumer even.

The spec is absolutely vomit inducing, though -- more ASN.1!

Arcanum-XIII• 3 years ago

Working for a broadcast company with a good chunk of news content, authenticating content is one of the major we face. It has always existed, but it’s getting worse and worse. That’s the goal of this system, not for consumer.

Regnore2• 3 years ago

I think ideally we'd get to a point where end users could easily see who signed an image so if someone was claiming an image was from cnn it could be validated. I imagine the end goal would be to put a warning on images that aren't from a signed source or maybe not displayed at all by default - similar to the uptake of https

blopker• 3 years ago

This is the first time I've heard of C2PA authentication[0]. It looks like they are digitally signing images from the cameras now to create a chain of authenticity. There's even TruePic[1] that is an authentication service that will show people if an image came from one of these cameras, overlaid on the image (or video) with some Javascript. Interesting way to fight AI images and deep fakes. They are also letting people register their deep fakes[2], but I'm not sure why someone would do that.

0: https://c2pa.org/ 1: https://truepic.com/ 2: https://truepic.com/revel/

Almondsetat2• 3 years ago

The new Leica camera already does it, give it a look for a working example already in the wild

choppaface2• 3 years ago

C2PA is more about tracking origin and edit lineage for e.g. press photographers. It does not determine if an image is a deepfake or not. Create a deepfake then take a picture of it with a C2PA camera, now you've got a C2PA-stamped deepfake.

But supposed you take a C2PA photo and then edit its contents with e.g. generative in-fill. The updated C2PA stamp from that action will get noted and can be audited later on.

chpatrick2• 3 years ago

Create a deepfake then take a picture of it with a C2PA camera, now you've got a C2PA-stamped deepfake.

Okay but then it's a deepfake from the BBC or some other known source, which would be bad for its reputation if people found out.

abdullahkhalids• 3 years ago

Both newspapers and social media routinely reconvert the original camera image into some smaller size or more suitable format. How is this system going to work in practice?

beenBoutIT• 3 years ago

Could it be used to track down journalists or prove that a certain journalist took a specific photograph?

Sounds like the photographic equivalent of guns that put unique stamps on their fired shells - theoretically making it easier to ID the shooter.

EMIRELADERO2• 3 years ago

Considering this might be targeted by nation-state adversaries for propaganda uses, I don't see the effectiveness, at least on that threat model. AFAIK even if the private keys are buried in some trusted computing chip, there's very little a focused ion beam can't do. And that's in an extreme security scenario, I doubt those cameras even reach that.

huytersd3• 3 years ago

What do you mean? An ion beam can read the private keys from the onboard chip?

jsmith993• 3 years ago

Assuming they use different embedded keys per camera (which is unfortunately unlikely) instead of the same key on every chip, this can be defeated by demanding to see the intact camera before accepting the signature. Ion beam assisted probing is a destructive process.

imhoguy• 3 years ago

I get a flashback of the yellow printed dots. Smells a privacy threat to me. I wonder if that fingerprinting can be disabled.

nonrandomstring2• 3 years ago

Useful for source authentication in news to combat fakes. I am sure if you don't want your identity associated with a picture there will be plenty methods to avoid this. Indeed some journalists will also need anonymity - but perhaps signed metadata on the GPS location/timestamp, so any camera for serious photo-journalist reporting will have to have those features.

Perhaps less interestingly, single frame exposure will defeat the accidental recording of sound into pictures recently reported to be a side effect of rolling shutters.

varispeed• 3 years ago

I think we are going to see more of this. I doubt this is about "deep fakes", as in reality the press doesn't care about it as long as it generates clicks and revenue.

It's more to do with surveillance and being able to more easily track someone trying to play investigative journalist, whistleblower etc. and show them their place.

For instance, if someone takes a photo of a big corporation exec giving a brown envelope to a politician and then another journalist show them to interested parties as a courtesy before publication, they could find out who took the picture and get them killed.

This is very dangerous and stupid what Sony is playing with.

zamubafoo• 3 years ago

Seemed fairly dystopian before you get to the examples. It also seems fairly trivial to bypass even if it's through crude brute force methods (ie. screenshots/copying framebuffers).

Is this essentially just enforcement through building a moat around editing applications?

lazycouchpotato• 3 years ago

Bing's Dall E-powered image creator uses Content Credentials as well.

https://i.imgur.com/7qDr0Q9.png

alphanullmeric• 3 years ago

When’s it getting put in a phone?

kart234• 3 years ago

it’s never made sense to me that there’s still not a single compact full frame camera. there are plenty of 35mm film cameras that you can literally slip in a pocket and still have pretty good lenses, what’s stopping a compact full frame camera these days?

https://casualphotophile.com/2019/05/17/ricoh-gr1v-film-came...

Darthy• 3 years ago

I've got the smallest digital full frame (the Sony RX1). Compared with your linked analog Ricoh GR1v, the Sony is bigger because of its much more capable lens. Putting the Ricoh lens on the Sony would have limited the quality a lot. It's a question of "do the elements fit together?".

kart234• 3 years ago

The sony lens is so big because its a lot faster. Sony also makes a pretty compact 35mm F2.8 lens comparable to what you could fit on a point and shoot. The elements definitely do 'fit together'.

https://electronics.sony.com/imaging/lenses/full-frame-e-mou...

coldtea• 3 years ago

There are a few Leicas (Q3), a Sony (RX) and some others.

On APS-C (Fuji) or compact-design-but-with-changable-lens there are a lot more options.

dboreham• 3 years ago

One issue is that you need a bunch of space behind the focal plane in a digital camera (the thickness of the sensor + its mounting system + PCB + cooling gap) while film cameras can mount the film (~zero thickness) right against the back door of the body. Another is that people expect EVF now, which requires more envelope volume than a compact 35mm OVF. Generally people paying $$ for a camera expect it to have removable lenses which adds again to the physical envelope.

There have been some Sony camera with fixed 35mm focal length lens and FF sensor. Like this: https://www.bhphotovideo.com/c/product/1316682-REG/sony_cybe...

kart234• 3 years ago

Theres lots of super thin digital cameras, an inch thin or less (coolpix, cybershot, etc). An iphone, which has a better screen, more capability and cpu power than a camera is extremely thin, what 'cooling gap'? Are you saying that the thickness of the sensor goes up as sensor size increases?

And theres plenty of $$ cameras with no removable lens, fuji x100 series, Sony RX1, leica Q, etc, like you linked.

selimco• 3 years ago

There's the sigma fp which is the smallest I believe.

vouaobrasil5• 3 years ago

Sony a7C. Very compact...

geerlingguy4• 3 years ago

It's still a bit of a thick back; compared to the thinner rangefinder film bodies it's a little thicker still.

What I don't like most about all my Sony cameras is the hand grip. It feels made for a robot, and I miss the nice organic shape of Canon and Nikon grips.

jsmith993• 3 years ago

There are pocketable FF camera with prime lenses and pocketable 1” sensor cameras with zooms. Those old 35mm film pocketable zooms had terrible apertures but a RX100M3 with a 1.8-2.8 aperture has a comparable effective aperture to some FF mirrorless with kit lens.

_ph_2• 3 years ago

Compared to what modern 35mm cameras can deliver, these cameras had very bad resolution. Yes, you could build such a camera today with a 35mm sensor, but the results wouldn't really justify the effort. If you want good compact cameras, get one of the smaller mFT cameras like the E-M10 or OM-5 and mount a pancake lens on it.

kart234• 3 years ago

“bad resolution”??? 35mm film can deliver 87 MP, more than any ff digital camera i know.

https://www.kenrockwell.com/tech/film-resolution.htm#:~:text....

justinator4• 3 years ago

A camera like this will make it a lot easier (and probably cheaper!) to verify who wins competitions, such as road bike races where a 200km race can be won by millimeters.

And oh hey! dpreview.com lives!

justinator4• 3 years ago

Here's an example of how the rolling shutter effects bike race photo finishes,

https://inrng.com/2012/04/photo-finish-camera/

justinator4• 3 years ago

And here's what's really going on with photos like this,

https://en.wikipedia.org/wiki/Photo_finish#Strip_photography

Toutouxc• 3 years ago

I don't think so. You've posted a link to Wikipedia in an adjacent thread that clearly says that photo finish cameras do NOT use traditional 2D sensors, but a "1D" single-strip sensor with very high refresh rate. They intentionally use an effect similar to rolling shutter where instead of the currently exposed row moving up and down the sensor, there is just one row and the photographed subjects move against the camera.

Yes, you could capture a similar photo by aiming a global-shutter camera at the finish line and firing the shutter exactly when the first contender triggers a laser beam or something, but that would be much more complicated and expensive than just capturing a single slice of space and letting time flow along the perpendicular axis.

justinator4• 3 years ago

would be much more complicated and expensive than just capturing a single slice of space and letting time flow along the perpendicular axis

I'm not quite sure. You're replacing a custom rig and technicians, with an off the shelf part. Sounds like it could be easier and cheaper (my point).

alpaca128• 3 years ago

Sony says doesn't compromise on ISO performance or dynamic range. [..] Sony isn't quoting a DR figure for the camera.

Who are they fooling?

Espressosaurus6• 3 years ago

No one that bothers to look at the minimum ISO spec of 250.

jacquesm2• 3 years ago

I remember a whole thread about dpreview no longer posting new articles and yet this one seems to be very recent.

https://news.ycombinator.com/item?id=35520495

Sony is rapidly becoming a major factor in the professional world as well. A family member works for a pro camera shop and he's absolutely lyrical about the Sony line. My biggest gripe is that it is hard to interface to the camera for things like shutter control, what looks like a USB cable really isn't (there are a ton of other wires running there that you can just barely see that control these kind of functions). But otherwise it's a very nice piece of gear.

cromulent• 3 years ago

Gear Patrol bought them, so DPReview lives on.

https://www.dpreview.com/site-news/8298318614/dpreview-com-l...

jacquesm2• 3 years ago

Ah cool, I totally missed that. Thank you!

cesaref• 3 years ago

Looking at this history of this problem, it first appeared with the adoption of focal plane shutters, which appeared widely with Leica 35mm cameras, and is a technology used by most SLRs. I know of earlier examples, the Speed Graphic large format camera uses a focal plane shutter, not sure when this was first used.

In the medium format world, lots of camera systems used leaf shutters, and these do not suffer from rolling shutter problems. The exposure is controlled by an aperture within the lens itself which opens the pupil to expose the film/sensor. The problem with leaf shutters is the minimum exposure tends to be limited to 1/500th of a second, although I believe there are some 1/1000th of a second leaf shutters in some lenses. Even some medium format SLRs have leaf shutters, for example, the Hasselblad 500 series cameras, and the Mamiya RZ67. Leaf shutters allow flash sync at all shutter speeds, which is why it was a popular technology for studio work.

In 35mm land there are some leaf shutter cameras, they tend to be fixed focal length designs. The olympus 35RD has one for example.

Anyhow, interesting tech, it's not relevant for the sort of photography I do, but i'm pretty sure the videographers will appreciate it!

wkjagt• 3 years ago

The Leica Q has a leaf shutter that goes up to (down to?) 1/2000s.

jeswin• 3 years ago

A handgun bullet travels 1200 ft per second. At 1/80000 of a second, the bullet travels 0.18 inches.

It won't be very good, but you can actually shoot a bullet with this. With enough light of course.

asimpletune3• 3 years ago

This might be a strange thought, but the idea of the global shutter got me thinking about the promise of a global shutter and the strange implications it could lead to regarding special relativity. I'm not an expert but, as I understand, one aspect of special relativity is that there is no shared now. Like, the idea of simultaneity is different than how we experience it, because two observers can literally witness a different sequence of events and there are no contradictions. (I hope I got that right)

In a traditional shutter, each row of pixels are read one at a time, so there is an inherit arrow of time. However, with a global shutter, each row of pixels is "exposed" simultaneously, theoretically. So what I wonder is what would be the implications of this with respect to special relativity.

For example, if a global shutter camera were used to adjudicate a close race, would it be possible for one row of sensors to witness a contradictory result with another row? Sorry if I'm not explaining this right but I'd be curious to hear what a more knowledgable person's thoughts on the matter are.

Espressosaurus6• 3 years ago

There are no implications regarding special relativity. The propagation speeds of the triggering signal are well understood. If for some insane reason it's not considered fast enough to simply ignore delays from one side of the chip to the other (wherever the sync signal comes in), it's straightforward to put in delay lines to ensure everything triggers at the same time to an accuracy that depends on the amount of silicon you want to lay down for those delay lines relative to the capacitors.

Most likely a couple nanoseconds one way or another don't matter (even at timescales of 1/80,000 s) and those ever-so-slight differences are ignored.

asimpletune3• 3 years ago

I meant in a theoretical sense, like as a thought experiment. If the shutter were an idealized, global shutter, where each row of pixels are exposed instantaneously, what would be the special relativity implications, if any?

wayfinder• 3 years ago

If two global shutter cameras take a scene at the same time, they would have the same image. If they don't, then they wouldn't.

Global shutter cameras are also not new. CCD sensors are global shutter and we used to use CCD sensors for cameras decades ago until we switched over to CMOS for most applications due to their larger size and better dynamic range. I have a global shutter HVX200 from 2005 in my closet.

asimpletune3• 3 years ago

So the whole point of what I was saying is that special relativity proves that whether two spatially separated events occur at the same time is not absolute and it depends on the observer’s reference frame. My question has nothing to do with engineering and wasn’t intended practically.

The point was to imagine light from some event, reaching two parts of the sensor at the same time, being exposed at the same time (ie the global shutter), and yet asking if those two parts of the sensor could show conflicting versions of that same event, since they are nonetheless separated by space.

nayuki5• 3 years ago

There is no problem. The sensor is a rigid assembly where all parts are motionless with respect to each other. Simultaneity is a well-defined concept for the sensor.

DrNosferatu• 3 years ago

Curious to see how it films a spinning airplane propeller.

Also, can the global shutter be turned off when you don’t need it, so you can get higher dynamic range?

amelius• 3 years ago

How is this accomplished? Is there a memory cell close to every physical pixel? Did they sandwich two dies together?

pestatije• 3 years ago

yes, its a 2 layer stacked-Cmos sensor

driggs• 3 years ago

Global shutter might be the most impressive feature, but also notable is that the a9 includes C2PA authentication metadata. This is a cryptographic chain of provenance on digital media, starting at the hardware camera itself.

In addition to provenance itself, C2PA allows for asserting that an image should not be used for AI training / ML mining.

https://c2pa.org/specifications/specifications/1.3/explainer...

nayuki5• 3 years ago

What stops someone from photographing a printed picture of a deepfake?

pkulak• 3 years ago

Nothing, but how do you make that look like a real photo?

I want to know how this process survives edits. Is it like HDMI, where I can't watch cable TV on my Linux machines because I don't have some stupid chain of certs from the hardware to my eyeballs? Will I no longer be able to edit my photos on Linux?

ngcc_hk• 3 years ago

For many it is irelevant. No doubt sony and video professional in sony cam would enjoy another upgrade opportunity. But for normal people, it is not the camera but also the lens etc. one has to think about. Not to mention still have F lens to migrate. (Or canon ... and Manu of these can be used by my Z9.)

lvl1023• 3 years ago

It’s about time Sony threw in a PCIe5/6 slot on these cameras. Ability to simply insert an internal 2-4TB drive would be very welcome. These CFE cards are ridiculously expensive for what they do.

cfn• 3 years ago

The latest Hasselblad already ships with an internal 1Tb SSD so there's hope.

e12e2• 3 years ago

[Sony] also says it will be introducing firmware updates to the a7S III and the a1, adding features such as breathing compensation. The a7S III will also gain DCI 4K capture. (...)
All three cameras will also add C2PA authentication metadata. C2PA is a combination of the efforts of the Content Authentication Initiative and the separate Project Origin initiative.

Wait, they're adding image attestation in software to existing models?

Avamander• 3 years ago

Funnily enough I can imagine this awful DRM being one of the few things that would help us avoid deepfakes and similar in the future.

M2Ys4U• 3 years ago

It's not DRM, it's optional provenance metadata.

So, think of it as cryptographically signing the image rather than encrypting the image.

jauntywundrkind• 3 years ago

Everyone wishes there could be new photography or videography features and Sony could with effort to reengineer some of these processing pipelines to do more (ex: Focus Breathing). but adding some workflow capabilities is off the main & intensive path of the device & easier to tack on.

e12e2• 3 years ago

As for price:

The a9 III will be available from Spring 2024 at a recommended price of $5999.
The 300mm F2.8 GM OSS has two XD linear motors to allow it to focus fast enough to work with the a9 III.
The 300mm F2.8 will also cost $5999 and will also be available in Spring 2024.

tlhunter• 3 years ago

The two products announced are mostly catered for professional photographers at the Olympics. The camera body and the lens are both very expensive, over $10,000 for the two combined.

That said, the global shutter is interesting, and will hopefully find its way into consumer grade products in coming years. Personally I'm excited about this "obsoleting" existing used cameras so that I can finally afford them.

touisteur• 3 years ago

Oh does this open software lenses and optical beamforming? The progress of acquisition tech is just staggering. ADCs in the last 10 years have just gone to incredible sampling rates, compacity... The future looks fun for the linear algebra signal/image processing people to go back to the drawing board: now that you have teraflops and these sensors available, let's start again.

Sony announces a9 III: first full-frame global shutter camera

Related Stories