The global shutter circuitry patented by Olympus (found via Egami)
A couple of days ago I told you via trusted sources that Panasonic has the plan to introduce the “global shutter” with the next GH3 camera. And not only Panasonic is working on it! Egami spotted an Olympus patent describing the noise reduction process on a sensor with global shutter. Global shutters can remove the typical effects from current sensors using the rolling shutter like exhibit smearing,skew, wobble, and partial exposure. Wikipedia explains it better: “Rolling shutter (also known as line scan) is a method of image acquisition in which each frame is recorded not from a snapshot of a single point in time, but rather by scanning across the frame either vertically or horizontally. In other words, not all parts of the image are recorded at exactly the same time, even though the whole frame is displayed at the same time during playback. This is in contrast with global shutter in which the entire frame is exposed for the same time window.”
According to Egami the Olympus global shutter sensor will also allow to have much sharper images (you can see an image comparison on their website).
67 Responses
Game changer for sure. Kudos to the winning company!
This sounds pretty cool, I just hope they don’t forget to work on designing the Pro-PEN with full manual controls, peaking and built-in EVF in the meanwhile 😉
(I know this is intended for video use) but could the electronic global shutter be used for still photos in place of the mechanical shutter? There would be several advantages:
-reduction in shutter lag
-no diffraction effects from shutter curtains
-no noise
-faster flash sync?
Don’t forget:
* No Vibration from shutter.
* FPS speed up
* All kind of multi-exposure techniques (NR, HDR, Super Resolution, stacking) facilitated.
I guess also:
-cheaper camera
-slightly lighter
-more reliable (mechanical shutter is probably least reliable part of a camera)
Just wondering.. If they can speed up the FPS to, say, 24, how would that be different from a movie? Or would that be called singularity?
Well, the GH2 does 40fps @ 4MP, you can consider that a video snap.
Personally I’d like to see 20fps @ 8MP instead, but with such resolution already (4MP), I see that as something much bigger! With the state of current stacking software I see it as an opportunity to choose the shutter speed AFTER YOU HAVE TAKEN THE PHOTO!!!
You now have the liberty of choosing whether to stack 1/10s of photos, 1/5s,…,1s
How short of a revolution is that?
“-no noise”
I know people talk about this being a Good Thing, but wouldn’t it be really weird having a *totally* silent shutter?
you could always have a fake shutter sound like most p&s, if you need it (i don’t)
I think I read somewhere that in Japan it is a law that cameras have to make noise on shutter release. I guess that seems well-intentioned, but it sure is a bother when trying e.g. to shoot pictures during a quiet classical concert.
Need we shutter noise ? 😉
Andy: The answer is Maybe. Video uses a subset of the photosites on a sensor. Basically you run about a 1 to 4mp sample to the video encoder. Note that the rolling shutter we currently have is because we can’t get even 1mp of data at 30 fps to the encoder simultaneously. So I suspect we’ll get global shutters for just the video stuff first. You don’t really need it for stills.
Shutter lag in cameras with full-blown mirror systems already runs less than 40ms, which is fast enough, IMHO.
Noise would tend to actually increase with a global shutter, I think, due to increased read noise. But perhaps someone has a way around that problem.
Faster flash sync is mostly a shutter problem, not a sensor problem.
@TH:
> So I suspect we’ll get global shutters for
> just the video stuff first. You don’t really
> need it for stills.
Don’t know about video, but stills…
Maybe we don’t need it, but camera manufacturers need it. Global shutter for them means huge cost savings (the last complicated mechanical unit (shutter) gone, not to mention assembling costs). Cameras can be smaller, more durable, and can be cheaper to manufacture and more competitive…
For the same reason mirrorless cameras are cheaper to manufacture (no mirror, prism assembly, and no complicated calibration on the assembly line needed)
Replacing mechanical components with electronic, to make equipment cheaper to manufacture is general trend, in goods manufacturing.
We users benefit (in case of cameras) smaller and cheaper equipment, silent, more durable… So I would say some of us need global shutter.
Some people (like me) have troubles adopting new concepts (like EVF instead of OVF), and consequently don’t need global shutter…
If camera have global shutter, will camera only have global shutter. 😀
Hogan ~ “Noise would tend to actually increase with a global shutter, I think, due to increased read noise. But perhaps someone has a way around that problem.”
Indeed there is
run multiple scans in the same exposure, now compare one overexposed scan with that of correct exposure. Like having 2 images several stops apart due to more gain. As noise generates in the shadows, now you have a reference file with a lot less noise that can enable you to accurately detect it and remove it from the correctly exposed image.
+10 Andy
I have little interest in the video benefits. There are significant benefits for stills. I think shutter vibration is a particular issue for the light undamped mft bodies especially with long telephotos.
Can anyone who understands the schematics and patent, explain how the new shutter works?
I guess this circuit is only a part of the whole construction. Looks like they use transistors and a capacity to realize the timing for the electronic shutter depending on variable voltage.
But it could also be a toaster 🙂
I don’t speak Japanese, but I understood the following from the translation/drawing:
The global shutter effect is achieved by resetting all the pixels (photodiodes 101) at once, with the exposure beginning after the reset ends.
During the exposure, the photodiode is floating, electrically speaking (transistor 107 is switched off), and charge is built up in the photodiode. At the next reset, the photodiode is connected to the power supply (by switching on transistor 107) so that the charge can flow off the photodiode, making it ready for the next exposure. (It seems weird to discharge something by connecting it to the supply voltage, but it is correct, since electrons flow towards the + side of the power supply.). So far this is just the normal operation of a CMOS image sensor.
The problem with the reset is that it causes the power supply voltage to “shake”, that is, noise is created.
Olympus’ invention is to gradually increase the supply voltage during the reset, in order to achieve a smooth discharching of the photodiodes, thereby reducing the noise. So they are solving a problem that arises only with electronic shutters. If mechanical shutters are used this is not an issue, because you can wait after the reset until everything has calmed down and then start the exposure by opening the mechanical shutter.
Of course, the charge in the photodiodes has to be transferred and stored, but the patent is not about that.
Hope this helps! Please let me know if something is not clear.
> Of course, the charge in the photodiodes has to be transferred and stored, but the patent is not about that.
Looks like transistor 102 and capacitor 103 are the storage device.
104..106 are for readout and reset of storage.
I think so, too. The drawing shows the whole cell, although the invention only seems to be about the resetting.
What to say, this is future. No mirrors and mechanical shutters ;). Cheers.
Seems a really useful feature.
Now does the A77 have this too? I’m orienting for my next camera for next year’s spring…
If a consumer camera has a global shutter, you certainly would have heard about it. So the A77 doesn’t have it.
Something similiar:
http://www.sonyalpharumors.com/sr5-a77-has-a-mysterious-electronic-first-shutter-curtain/
I guess every camera company is somehow experimenting with global shutters. But so far, no one has made a breakthrough, and I wonder why Pana or Olympus should be the ones to do it.
Remember, the GH2 was supposed to have a global shutter, too.
I does actually. Only it won’t work at full resolution!
I think in GH2 (fast continuous shooting) it’s still rolling shutter
The 40FPS @ 4MP mode is definitely not using the mechanical shutter, but that doesn’t mean it is a global shutter. The image sensor performs the shutter operation, and it could either be a rolling shutter or a global shutter, depending on how the pixels are reset (per line or all at once).
It probably isn’t a global shutter, because marketing would have told us if it was (global shutter written all over the GH-2 box ;-).
Good point ThomasS. We are confusing electronic shutter with global shutter. The former allows silent operation, fast flash sync, HDR, no vibration, high FPS. The latter is required to avoid the rolling shutter/jello issues that the videographers want.
I believe Duarte is referring to the special cropped video mode the GH2 supports. It does appear that there is no rolling shutter when using it.
No Thom.
Gasper is right!
I was really thinking about the 40fps @ 4MP mode. I just though of the electronic shutter as in opposed to a mechanical one and mistakenly assumed electronic = global!
Thanks everyone for the clear up!
You definitely won’t hear a rolling shutter if it is implemented by the image sensor (by resetting pixels in “waves”, from top to bottom).
Or do you mean you don’t notice the artefacts created by a rolling shutter in the images?
Hi Thom: The GH2’s wonderful ETC (extra tele conversion) mode feature has noticeably less rolling shutter (skew, jello, etc.) than the GH2’s already very good normal video modes, but it still has some.
ETC records less aliasing, no line skipping, and less rolling shutter, but it still records varying amounts of these — plus a small amount of additional video noise — compared to normal GH2 recording.
If the GH2 had (or the GH3 has) a global shutter, of the issues mentioned above, only rolling shutter artifacts would be eliminated.
Cheers.
@Admin:
Saying a global shutter will allow the camera to “to have much sharper images” might be a bit misleading. You might want to re-phrase that to “to have less blurry images” because what those images show is clearly a problem with camera shake. A global shutter will surely help against such problems but it can never make the images sharper than they will be in appropriate capture conditions (no camera shake).
There is *always* camera shake induced by an internal, mechanical shutter. It can be minimized but not eliminated. In “appropriate capture conditions” with all else equal, a non-mechanical shutter will produce an image with finer detail which everyone considers sharper.
I’m sure when mechanical shutters are designed, symmetrical cancellation forces are taken into account. Don’t forget the mirror (where you can’t have a symmetrical design) is already gone. I say this because in some extensive IS tests I’ve performed on my E-510, a mirror lock-up wouldn’t benefit the image sharpness over a tripod mount (and we all know the mirror is a much bigger pain in the ass than the shutter).
In “appropriate capture conditions” (with a fast shutter speed) with all else equal, I doubt that images put to a blind test would reveal any sharpness advantage to a global shutter.
And I reiterate that the linked images suffer from camera induced shake not shutter vibration as they have a clear horizontal predominance.
Is it for video only or also for taking picture? If it is for taking picture, is it mean mechanical shutter could be removed and no annoying 1/160 sec shutter speed limit with flash?
I’d rather stick with an audibly perceptible shutter and take a focus peaking feature instead, thanks.
…but then again, cameras with global shutter will certainly offer 12 user selectable Art Shutter Sounds to choose from…
Art shutter…hooooooo! That was a good one, lol
+1 You could program different sounds for different shooting modes. Think of the possibilities! 😉
@ThomasS … That’s the kind advertising would be splashed all over the box!
If there were an option just to have a very quiet sound, just for shot confirmation and be able to disable it completely, would work best. Like the ever-so-irritating focus beep.
Why not include a wav player option…. Set shutter noise to:
Leica,
Nikon D3S,
Canon 1D,
Shotgun,
Colt 45,
AK47….
And voice recorded too:
– yoink
– d’oh
– Khaaan
I think i will have some trouble too gettin used to a total silent shutter, will this make the electronic shutter sound an always enabled option then? 😉
Not me. Global shutter allows you to do several new things with a camera. Focus peaking helps you do something we have been doing pretty effectively already.
T**ser!
Lets hope its not an either/or situation…. lets hope we get both!
About time camerase became fully electronic!
I hope you live long enough to witness it in the real world :>
A global shutter would offer many possibilities which can currently be achieved only through extensive post-exposure processing. However, personally I’m perfectly comfortable with a lowly mechanical shutter that goes “click” on every exposure, 3 fps (actually, I never use sequential exposures) and limited DR. And the rolling shutter symptoms in video capture are the least of my worries. Photography used to be simple and AFAIC it better stay that way.
Spoken like a true crusty old man. 🙂 Taking photos has always been easy, even in the film days. You just point and shoot, right? Still the same now, right? Some of us do try more creative and complex techniques that take advantage of new technology, but to each his own.
“Photography used to be simple and AFAIC it better stay that way.”
Out of interest, when did it used to be simple? I unscrewed a Pentax MX once – woooooow….
Sneye may be right especially if there are big compromises eg
Lower IQ/DR
Shutter lag
High battery consumption
Etc
Good news! Now put this in the E-50 body and steal Sony’s transparent mirror and viewfinder, and there’s the new 4/3 camera 😀
No need to even steal Sony’s transparent mirror, the e330 already had one.
No, it didn’t. It had a dedicated sensor for live view.
There was a transparent mirror that split the light between the dedicated live view sensor and the OVF….
http://www.imaging-resource.com/PRODS/E330/E330A.HTM
ok, it’s not the main mirror that’s transparent but it’s there.
Yes, and also a transperant mirror after portaporta OVF on live view B ca. 50% to minni sensor and 50% to eye, but in live view A is a normal live view dircht to sensor.
…any way, the transparent mirror technology is Canons stuff, not Sonys
No shutter (less moving parts) likely also means longer life, and possibly lower cost.
I hate shutter noise, awaiting a noise free camera!!
I would love to have a Foveon-like sensor more than the global shutter. My -,02€
+1
Don’t get confused, let’s say it together:
GLOBAL SHUTTER != ELECTRONIC SHUTTER
Importan reason for 2012 is a year for global shutter, is Kodak patent on global shutter from 2001, is over teen year. 😉
That’s the feat that I’ve waiting for so long. Right now I’m also considering the NEX-7 for the future, but with global shutter, it will be a m4/3 for sure. I would like to see peaking focusing though it’s a pretty goof feat in the NEX cameras.
If they can keep current GH2 capabilities and the ONLY upgrade is the global shutter, I am THERE! Absolutely THERE.
The CMOS distortion is the reason my professional video camera is still CCD and both my digital still cameras are CCD. I like some of the spiffy features of CMOS (very fast FPS) but refuse to accept the image distortions CMOS engenders.
http://ieba.wordpress.com/?s=cmos+distortion
A importan reason for 2012 is the year to global shutter, is Kodak patent on global shutter from 2001 is over ten year old. 😉