Global Shutter Coming to Canon DSLRs? [CR1]

[raptor3x]

This is a step in the right direction for Canon and I'm hoping a firmware update 'might' bring this to the table.

Fujifilm just released their new line of mirrorless cameras that have ELECTRONIC AND MECHANICAL shutters. You can either use one or the other depending on shutter speed needed. Their shutter speed limit is 1/32,000 of a second. Fuji also just provided firmware updates for two of their previous models to incorporate this new electronic shutter feature. Now, how great is that?

My point is, it can be done and is being done now with some manufacturers. The electronic shutter is totally silent.

The electronic shutter on the X-T1 is neat but it causes pretty severe rolling shutter effects even with relatively minor motion. Global shutter is a completely different animal.

 

[LetTheRightLensIn]

What's the point of having 30fps when you have video shot at 30fps? Doesn't the 1DC cover this? Or is this basically what the mirrorless cameras have, just faster? they have very fast frame bursts.. slightly confused?

Various points:

18+MP is a LOT more detail (with a LOT more reach for sports and wildlife too) captured than 2MP or 8MP.

As far as compression and RAW and so forth, you could of course allow those all as video options too so nothing gained there per se.

The big thing is, aside from the detail and reach, that none of the DSLR have global shutter so you get issues that are not acceptable from stills from video in too many important scenarios.

The 1DC definitely does do anything this would at all because: no RAW video so you'd be stuck with essentially in camera processed 8bit JPG images for stills! it applies compression, no lossless modes. 8MP is simply a lot less detail 18+ MP, especially after the compression.

 

[canonvoir]

A Global Shutter would keep Canon out front no doubt and every strobist I know would be all over that (more so in 5D4 form not 1DX of course).

30 fps would be great! I just hope they can get a better select and delete function "in camera".

 

[Frage]

What's the point of having 30fps when you have video shot at 30fps? Doesn't the 1DC cover this? Or is this basically what the mirrorless cameras have, just faster? they have very fast frame bursts.. slightly confused?

its shutter speed will typically be roughly 1/frame rate, or at least somewhat slow... so you get a lot of blurred shots. taking 30fps of 1/8000th second shots is another thing entirely.

Shutter speed is a very good point, but I do not believe 1/8000th will be possible by now.

 

[rfdesigner]

What's the point of having 30fps when you have video shot at 30fps? Doesn't the 1DC cover this? Or is this basically what the mirrorless cameras have, just faster? they have very fast frame bursts.. slightly confused?

its shutter speed will typically be roughly 1/frame rate, or at least somewhat slow... so you get a lot of blurred shots. taking 30fps of 1/8000th second shots is another thing entirely.

Shutter speed is a very good point, but I do not believe 1/8000th will be possible by now.

If we place relatively non-photosensitive capacitors under each photosite, but electronically after the immediate amplifier (so strong signal and hence less impact by a stray photon), and implement a sample and hold function around it, then you can have a global electronic shutter. The problem is that you'd need to do this low down in the silicon and still build the photosites above it.

Doing that would allow you to have very very fast shutters.. well over 1/8000th as there's no moving parts.

 

[Tugela]

What's the point of having 30fps when you have video shot at 30fps? Doesn't the 1DC cover this? Or is this basically what the mirrorless cameras have, just faster? they have very fast frame bursts.. slightly confused?

Video has two disadvantages.

its resolution is usually less than still frame modes/cameras

its shutter speed will typically be roughly 1/frame rate, or at least somewhat slow... so you get a lot of blurred shots. taking 30fps of 1/8000th second shots is another thing entirely.



What I'm scratching my head about is how are they doing it.. liquid crystal?.. double layer CMOS sensor (with a hidden layer? so the image can be transferred to an insensitive layer when integration time is enough).. Somewhere in a box I have an FT18 CCD sensor with 2048 x 1024 sensor, with half the CCD covered, so you can take a 1024x1024 image, then shift it to the dark area and then read it out at leisure. But that's expensive in terms of silicon and large, if that could be replicated vertically it would be interesting.

I imagine that you could probably do it with a buffer associated with each photosite, so that the buffer could be read independently of the sensor currently acquiring data. That would allow data to be acquired globally but read into the processor sequentially.

 

[Lars]

30fps? Would that be in Live view only?

Because having the mirror flip up and down 30 times per second is going to be ... interesting. And wear out the mechanism pretty fast, I would think.

 

[preppyak]

What's the point of having 30fps when you have video shot at 30fps? Doesn't the 1DC cover this? Or is this basically what the mirrorless cameras have, just faster? they have very fast frame bursts.. slightly confused?

The mirrorless cameras (like every other EOS with video) use a mechanical shutter for stills and an electronic shutter for video.

The problem with the electronic shutter is that is reads off line by line in a progressive wave accross the sensor.

Whilst it is easy to make the read of each individual read very fast (thereby equivalent to only being 'exposed' for 1/50th, 1/250th, 1/2000th of a second) the speed at which the scan passes over the entire chip is relatively slow.

This means that the moment of the last line being scanned is visibly behind the first and intermediate lines being scanned.

You may also have heard this being called 'jello shutter'.

If you have a dslr with video mode, do a whip pan left or right. Vertical lines become diagonal lines as the slow scan rate of the sensor is betrayed.

In a global shutter the entire frame is read in the one instant. So these diagonal lines disappear.

Now the if it's doing that to diagonal lines, what else is it doing to other details in the image?

So why is it a problem?

Well, increasingly press photographers have to also provide video, and with the advent of 4K video decent frame grabs become viable. You could fill a magazine cover with an 8MP frame grab from UHD footage.

But not if all the details are wavy and distorted.

So, there are two benefits... it will make video a lot better, rapid camera movements are now possible ...it will make video grabs a lot better too. Something Canon must see a requirement for in certain user segments.

And I think they are right.

And implement Global Shutter on a camera that shoots 4k RAW video and suddenly you have a camera that can take 8-10mp stills, in RAW, at 24-30fps. Your limitation is no longer the shutter, its the buffer.

How this works within the confines of auto-focus is, I'm sure, it's own interest problem. Its a non-issue on most 4k production cams because you are pulling manual focus anyway. But if that comes with auto-focus, thatd be impressive as hell, even at 24fps

 

[NancyP]

Maybe I have this wrong, but my concept of "global shutter" is that all pixels are turned "on" to collect photons simultaneously (a microsecond), then turned "off" simultaneously. The pixels hold charge and are dumped line by line into the buffer. Some pixels have to hold onto their charge longer than other pixels, assuming the process of data dumping (reading) takes some appreciable unit of time (10 to 50 microseconds). Pixels should be devoid of charge at the end of the data dump.

If that is so, there should be no "rolling shutter effect".

 

[Tinky]

The 1DC definitely does do anything this would at all because: no RAW video so you'd be stuck with essentially in camera processed 8bit JPG images for stills! it applies compression, no lossless modes. 8MP is simply a lot less detail 18+ MP, especially after the compression.

8MP sounds a lot less than 18mp. But remember we are talking about areas, inverse square. It might be more than double the area, but the difference isn't as stark, orientation for orientation as you may think. For newspaper print resolutions (far lower than 300dpi) 8MP is huge, for glossier magazines, it's still all you need to more than fill an A4 page.

And besides, for press work, in fact, for most work going online, even 8MP is serious overkill.

I can't argue for a second that raws are inferior to jpegs on any technical level, but I would say that in my experience of working along side press photographers for 8 years, the guys shooting for a national UK newspaper never shot RAW even in the studio. There wasn't the time to process, there wasn't the time for picture editors to download the latest versions of camera raw etc. It was all well set up cameras and jpegs to be sent over 3G phone networks.

As hobbyists we have the luxury of time on our hands to get things exactly the way we want them. For news professionals you have to rely on experience and an expeditious workflow. Sometimes 8bit jpegs are all you need.

 

[Andrewccm]

I believe some people don't fully understand the difference between shutter speed and frames captured per second. Not this same thing. Using video for stills in relation to DOF produced by aperture/shutter/ISO ratios does not pertain to FPS. Maybe I am stating the obvious. I saw a couple of comments earlier that made me wonder.

 

[Tinky]

What's the point of having 30fps when you have video shot at 30fps? Doesn't the 1DC cover this? Or is this basically what the mirrorless cameras have, just faster? they have very fast frame bursts.. slightly confused?

Video has two disadvantages.

its resolution is usually less than still frame modes/cameras

Except that resolution is measured differently.

For example, when 1080p is played back, there are 2,073,600 pixels but they're a combination of RGB.

Your 20MP DSLR counts each R, G and B (and G as individual pixels (except if you're Foveon) and does some fancy math to get 20,000,000 combinations of RGB.

If they counted video pixels like they do DSLR pixels, 1080p would be 8MP and 4k would be 33MP.

Sorry. Incorrect.

This would be true of a traditional eng camera with dichroic prism and 3 image devices dedicated to each wavelength, on a dslr you don't. You have a bayer array sensor with some computing hi-jinx to smooth out the bumps. This is true for stills and for video. There is some arguement that the downsampling helps to smooth out the bumps further, but in fact you have the same starting point. A bayer array.

Think of it this way, if video was unique in having RGB components, then why would your DSLR have adobe RGB or sRGB options? Why wouldn't all your still images just be in black and white.

When Sony or Sigma put three of their sensors round a massive s35 dichroic prism I will get excited. Bayers leave me just a little cold in the meantime.

 

[benperrin]

It has certainly been great watching innovations happen like hss and hypersync so that we can push our equipment further, a global shutter that increases sync speed and possibly reduces noise would be most welcome. I thought this rumour has been around for a while though. Certainly 1/200 and sometimes not even that fast has felt slow compared to nikon.

 

[Lawliet]

This rumor seems farfetched, though. If Canon could create a self contained camera that could continuously record RAW and compressed images at 30fps on a global shutter, it would have a huge impact on both the video and photography markets. Nothing comes close right now. The 1DC is a pale imitation since it can only record non-continuous 12fps RAW and 24fps compressed at APS-H crop on a non-global shutter.

The Dragon records 6K at 100fps, or extrapolated to 8k and a 3:2 aspect ratio still 40fps at full resolution. Or the rumored 52MP at 30fps. Global shutter included,the target audience isn't to fond of yello (behind the lens at least).
Or in the more consumer orientated segment you get 6700MP/s capacity, enough to go through 8K at >120fps, in a package smaller then the 1-series.

For raw storage you'd need a breakout to an SSD-raid though.

 

[Orangutan]

This rumor seems farfetched, though. If Canon could create a self contained camera that could continuously record RAW and compressed images at 30fps on a global shutter, it would have a huge impact on both the video and photography markets. Nothing comes close right now. The 1DC is a pale imitation since it can only record non-continuous 12fps RAW and 24fps compressed at APS-H crop on a non-global shutter.

The Dragon...Global shutter included

Near as I can tell, the Motion Mount add-on is what gives the Dragon its global shutter via a liquid crystal shutter. It costs an extra $4k and eats a stop of light as an ND filter. That's only useful in bright natural light or controlled light. How is that comparable to GS on a stand-alone 1DX successor?

 

[jeffa4444]

The Red Dragon does not natively have a global shutter its a rolling shutter as is the Arri Alexa. The Sony F65 has a global shutter as does the Sony F55. Skew is produced by rolling shutters NOT global shutters. If say your shooting with a global shutter and you pan down quickly shooting a chandelier you will get the light dragging down but overall a global shutter is superior to a rolling shutter. In practise we have found the Sony F55 has the least shutter induced artefacts.
If Canon are contemplating a global shutter this may lend more weight that the sensor maybe a Sony sourced sensor, and I would agree CFast would make a better recording medium for the write speed. Arri were the first to adopt CFast with the Amira.
What is going to be interesting is if the camera has a Anti Aliasing filter or not given this could be the weakest link.

 

[dash2k8]

Um... global shutter... AWESOME!

 

[Perio]

No, no, no. I'm honestly hoping Canon won't release this camera. Otherwise my gf would get crazy when she knows I'll purchase it.

 

[Lee Jay]

I'd like to hear why people want a very fast sync speed. I know quite a lot about this topic and can see direct applications for sync speeds up to about 1/1000th, but at that point applications get a lot more limited.

 

[Tinky]

I'd like to hear why people want a very fast sync speed. I know quite a lot about this topic and can see direct applications for sync speeds up to about 1/1000th, but at that point applications get a lot more limited.

I blame all these high iso cameras haha. Whats the point of having f1,4 lenses and 106,000 speed if you never use it?

I wish somebody would bring out a camera with a lower base iso instead, 12, 25, 50? Super clean. I don't need a high iso much more than 3200 in any case...

I know I could ND, but I like a bright viewfinder and fast af...