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Canon develops 35 mm full-frame CMOS sensor for video capture

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Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#41

Post by vanderZwan »

theatrus2 wrote: post #31
prof_hobart wrote: post #23

Earlier quoted context omitted.

But they aren't the only two options. With the quality of lens on the average compact camera for instance, I struggle to see any real noticable improvement above around 5 MP.

Lenses are very constrained by physics, and cost. Ground glass and more exotic materials are expensive to produce - injection molded plastic isn't. A high MP sensor is miles cheaper than an upgraded optical system.

And a cheap lens with low optical resolution makes a higher number of pixels effectively useless, so it's still a strange development.

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#43

Post by ominous_prime »

baq wrote: post #38
ominous_prime wrote: post #15

Earlier quoted context omitted.

of course we would, but photographers wouldn't be too impressed with only capturing 1920(?)x1080 resolution. This gains it's light gathering abilities by simply having much larger "pixels" on the sensor, which can collect more photons. This is the same principal used on the highest end canon eos body, the 1DX, which has slightly lower resolution than the 5DmkIII in order to gain sensitivity.

Native resolution of this baby looks to be 864 mm^2 / 19 micron^2 ~= 45MPix, in line with the latest Nikon and with rumors of high-density FF Canon. The innovation here is noise reduction and not the sensor itself... obviously Canon will charge an arm an a leg for that video camera - and won't ever make it into a DSLR to not cannibalize their profits.

I'm fairly certain they meant that pixels are 19µm on a side, not in area, since they state:

> 7.5-times the surface area of the pixels on the CMOS sensor incorporated in Canon's top-of-the-line EOS-1D X and other digital SLR cameras

That puts a 35mm sensor right around HD video resolution, or in the 2-2.1MP range.

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#44

Post by quantumstate »

vanderZwan wrote: post #41
theatrus2 wrote: post #31

Earlier quoted context omitted.

Lenses are very constrained by physics, and cost. Ground glass and more exotic materials are expensive to produce - injection molded plastic isn't. A high MP sensor is miles cheaper than an upgraded optical system.

And a cheap lens with low optical resolution makes a higher number of pixels effectively useless, so it's still a strange development.

Higher pixel counts give less noise assuming the total light collection area is the same. Normally you get a bit less light collection area due to the gaps between pixels with a higher resolution sensor but overall I think higher pixel count generally wins, especially when working at the low iso end. So as long as the cost is reasonable why not stick lots of pixels in.

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#45

Post by scottoller »

davidjohnstone wrote: post #21
eksith wrote: post #13

Earlier quoted context omitted.

Didn't he use the same lenses used by NASA on the cameras for the Apollo missions? I think the larger aperture gave better low-light exposure during the candlelit scene (and may have inadvertantly fuelled conspiracy nuts that think the moon landings were a hoax because they think the sunlight reflected off the regolith was a secondary light source).

Yes, an f/0.7 aperture is a ridiculously wide aperture (thus, it lets in a lot of light[1]), two stops brighter than f/1.4 (a "stop" means a doubling of the amount of light; f/1.2 lenses are the fastest lenses commonly available, and they'll cost around $2k), or four stops faster than f/2.8 (which is what the fastest commonly available zoom lenses are, and they're expensive too). Leica make a very rare f/0.95 lens th…

There's also a discontinued Canon f/1.0 that some rental places still have. I shot some stuff with it, and it's pretty amazing to play around with. Even with that though, we had to expose for at least 4 seconds at ISO 1600 to get legit star exposures. I've always fantasized about being able to shoot handheld video of the Milky Way, I'm happy to see that the technology now exists!

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#46

Post by mikec3k »

regehr wrote: post #20

I always find it depressing when I take a picture by moonlight and it ends up looking very much like a picture taken by sunlight, as opposed to looking like the scene looks to our eyes. Always have to keep in mind that a CCD != rods and cones. Sensitivity is nice but as far as I'm concerned, dynamic range is the main thing that's needed in digital photography. DSLR sensors have gotten much, much better over the last…

That's a result of how metering works - it assumes you want a brightly lit scene. You'll either need to use manual exposure or use one of the spot metering modes, where it measures only the brightness of a focal point rather than the overall scene brightness and tries to compensate.

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#47

Post by pixelcloud »

davidjohnstone wrote: post #21
eksith wrote: post #13

Earlier quoted context omitted.

Didn't he use the same lenses used by NASA on the cameras for the Apollo missions? I think the larger aperture gave better low-light exposure during the candlelit scene (and may have inadvertantly fuelled conspiracy nuts that think the moon landings were a hoax because they think the sunlight reflected off the regolith was a secondary light source).

Yes, an f/0.7 aperture is a ridiculously wide aperture (thus, it lets in a lot of light[1]), two stops brighter than f/1.4 (a "stop" means a doubling of the amount of light; f/1.2 lenses are the fastest lenses commonly available, and they'll cost around $2k), or four stops faster than f/2.8 (which is what the fastest commonly available zoom lenses are, and they're expensive too). Leica make a very rare f/0.95 lens th…

Any f-stop below 1.0 is pretty incredible. Kubrick filmed that scnee with JUST candle light.

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#48

Post by tomkinstinch »

TheAnimus wrote: post #7

I wouldn't mind a better bit of info about the sensor! For instance I'm guessing its a bayer filtered job, to keep the sensativity (at the expense of sharpness of say Sigma Foveon). But I can't believe they have just had such an improvement by switching to larger wells and more sensativity, do they have some cunning time domain based filtering too. One advantage digital sensors have is that they can exclude certain b…

I wonder if they are using a bayer mask with an RGBO pattern (R, G, B filtered wells, and an open channel in each repeating subunit).

Kodak has the patent, so they may have been able to acquire or license it at low cost.

http://web.archive.org/web/20070720002510/http://johncompton...

Re: Canon develops 35 mm full-frame CMOS sensor for video capture

#49

Post by CountHackulus »

topbanana wrote: post #11

Is this a color sensor? The high end astrophotography sensors tend to be monochromatic, with a filter wheel placed in front of the sensor. That way, each well has 3 times as much chance of seeing a photon.

All sensors are monochrome just with red, green, and blue filters over pixels in what's called a Bayer pattern. The only real exception to this rule that I can think of is the Foveon sensor.
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