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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

#71

Post by Sharlin »

baq wrote: post #54
ominous_prime wrote: post #43

Earlier quoted context omitted.

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.

This same sentence also says: >The newly developed CMOS sensor features pixels measuring 19 microns square in size So there is a possibility that the pixels are merged by the image processor after data is read off the sensor.

I, at least, read "19 microns square" as "19 microns times 19 microns", that is, (19 µm)² = 361 µm².

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

#72

Post by mayank »

davidjohnstone wrote: post #9

For comparison, the Nikon D4 (a digital SLR) can shoot video at ISO 204,800, and it can resolve details in the dark beyond the ability of the eye, and I suspect this new sensor is more sensitive — or, at least, far more noise free — than that. EDIT: Judging by some photos I've taken of the night sky, with an f/2.8 lens and with a shutter speed of 1/50s, you need an ISO of around 300,000 to get enough brightness. If o…

Fascinating. Looks like there were only 10 of those f/0.7 lenses made, 6 of which went to NASA to photograph the moon.

http://en.wikipedia.org/wiki/Carl_Zeiss_Planar_50mm_f/0.7

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

#73

Post by prof_hobart »

klodolph wrote: post #55
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.

If you're looking for a 20% improvement from 5 MP to 6 MP, you won't find it. It's really more like a 10% improvement. How many MP does a camera have, if it has twice the resolution of a 5 MP camera? It has 20 MP, not 10. There are also physical limits. The angular resolution depends on the lens aperture size. Smaller cameras have smaller lenses with smaller apertures, which must have lower angular resolution just be…

>The lens is f/3.9, which gives a resolution of about 400 lp/mm in visible light

Assuming that you've got a perfect lens. As you say yourself "You must not open the lens fully", in which case the f/3.9 is irrelevant.

And even stopped-down, the glass (of which there's several elements in the average compact's zoom) is rarely of the highest quality. All of this makes for an effective resolution some way short of the figures you're quoting.

The quality of the lens can make a huge difference. On my main DSLR, the difference in quality between, say, the 50mm f1.2L and and an identical shot taken with a bog standard 17-85 f/4, even at the same f-stop is vast. If the cheaper lenses on DLSRs aren't able to really give enough quality to fully take advantage of higher MP, I'm not quite sure why you'd think that the ones on a compact would be.

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

#74

Post by graycat »

So, with all the critical details here about CCD sensors, you expert guys are telling me that I should not rush out and spend $10 K, $20 K, or whatever for the latest Nikon/Canon single lens reflex with a CCD sensor and a bag of lenses and, instead, keep my old Nikon Nikormat with its bag of Nikon lenses?

Let's see, opening the bag for the first time in a while, I have a Nikkor 200 mm f4, a Nikkor 105 mm f2.5, a Nikkor 55 mm f3.5 macro (good for closeups and general usage) with an extension tube for getting even closer, and a Nikkor 50 mm f1.4. Ah, I guess the f1.4 is for taking shots of the girlfriend in her little cocktail dress sitting at the candle lit romantic dinner table waiting for the rest of the evening! Or maybe I should be sitting at the table taking the picture as she comes in with a frilly apron over her cocktail dress and carrying a serving tray with her hand made Sachertorte mit Schlagobers (whipped cream)?

Also in the bag is a Honeywell strobe light: It uses a 900 Volt dry cell battery if can find one and otherwise just uses the A/C adapter. The recharge time on the A/C adapter is fast.

I suspect I will be able to buy film such as Kodak Kodacolor for a long time, but processing is an issue: I've had Sam's Club start with my Kodacolor 35 mm and return to me a CD with JPG images with 1818 x 1228 pixels which seems to be a little below the resolution of the best of the Nikon equipment. At one time Kodak offered Kodak PhotoCD with much higher resolution.

Any suggestions? What about getting good processing and scanning to JPG of the film? Sounds like my old Nikon equipment is still competitive with newer single lens reflex cameras with CCD sensors and roughly 35 mm image width?

E.g., on resolution Dalsa made a CCD image sensor with 48 million pixels, a light detection rectangle 36 x 48 mm, i.e., much like 35 mm film in my Nikon, with each pixel a square 6 microns on a side, capturing about 55,000 electrons per pixel, and, net, 6 K x 8 K pixels. Sounds good until notice that apparently each pixel is for just one color, red, green, or blue, and they use a 2 x 2 array of four such pixels, one red, one blue, and two green, for one 'color' pixel. So, in such 'color' pixels their sensor is 3 K x 4 K and, thus, not necessarily a lot better than 35 mm film?

Where am I going wrong?

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

#75

Post by minikomi »

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…

As a 70s canon rangefinder nut, I feel it is my duty to point out that Zeiss was not the only one responsible for a 0.95 lens http://japancamerahunter.com/2012/01/the-incredible-canon-50...

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

#76

Post by xyzzy123 »

klodolph wrote: post #63
seunosewa wrote: post #53

Earlier quoted context omitted.

It is simply not true that noise increases as pixel size increases. The exact opposite is widely known to be true. See this page, for example: http://firmitas.org/Sensor.html

I was actually just paraphrasing the linked page from Canon: > In addition, the sensor's pixels and readout circuitry employ new technologies that reduce noise, which tends to increase as pixel size increases. The linked page is pretty sketchy, it mentions lenses but not optics. Optical resolution will be limited regardless of whether the lenses are perfectly polished. It's hardly irrelevant too, with modern optical…

Well they're describing the sensor, not optics, so that part is forgivable.

Also, they're describing a 35mm sensor. This thing will work with existing 35mm film optics, and (apart from physical properties) that's a big part of why the sensor size is interesting.

Would be nice if there were more technical details, but I guess that's press releases for you.

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

#77

Post by rorrr »

davidjohnstone wrote: post #9

For comparison, the Nikon D4 (a digital SLR) can shoot video at ISO 204,800, and it can resolve details in the dark beyond the ability of the eye, and I suspect this new sensor is more sensitive — or, at least, far more noise free — than that. EDIT: Judging by some photos I've taken of the night sky, with an f/2.8 lens and with a shutter speed of 1/50s, you need an ISO of around 300,000 to get enough brightness. If o…

Why don't you post a D4 video at ISO 204,800, so we can all laugh at it.

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

#78

Post by klodolph »

prof_hobart wrote: post #73
klodolph wrote: post #55

Earlier quoted context omitted.

If you're looking for a 20% improvement from 5 MP to 6 MP, you won't find it. It's really more like a 10% improvement. How many MP does a camera have, if it has twice the resolution of a 5 MP camera? It has 20 MP, not 10. There are also physical limits. The angular resolution depends on the lens aperture size. Smaller cameras have smaller lenses with smaller apertures, which must have lower angular resolution just be…

>The lens is f/3.9, which gives a resolution of about 400 lp/mm in visible light Assuming that you've got a perfect lens. As you say yourself "You must not open the lens fully", in which case the f/3.9 is irrelevant. And even stopped-down, the glass (of which there's several elements in the average compact's zoom) is rarely of the highest quality. All of this makes for an effective resolution some way short of the fi…

> If the cheaper lenses on DLSRs aren't able to really give enough quality to fully take advantage of higher MP, I'm not quite sure why you'd think that the ones on a compact would be.

You might be surprised at the quality of some of the P&S lenses. There have been excellent lenses on cheap fixed-lens P&S cameras for decades: a modern example is the Sony Cyber-shot DSC-RX100, an older example is the Yahsica Electro series from the 1960s. From resolution tests you can find modern P&S cameras with soft lenses and you can also find ones with real, honest 10+ MP resolutions. You don't need to trust my math, you can go check out test shots online.

> As you say yourself "You must not open the lens fully", in which case the f/3.9 is irrelevant.

I also wasn't really explaining things fully with the maxim. Opening the lens reduces diffraction and increases aberrations. A few good lenses will open all the way to, say, f/2 and still get sharper as you open them up. Some terrible lenses aren't sharp at f/8. However, the trade-off is different at different system sizes. For a P&S, wide open might be the best way to go. For MF and LF, you'll probably want f/11 or f/22 to start with, as ridiculous as that sounds. Of course, this assumes you want maximum resolution.

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

#79

Post by cuu508 »

graycat wrote: post #74

So, with all the critical details here about CCD sensors, you expert guys are telling me that I should not rush out and spend $10 K, $20 K, or whatever for the latest Nikon/Canon single lens reflex with a CCD sensor and a bag of lenses and, instead, keep my old Nikon Nikormat with its bag of Nikon lenses? Let's see, opening the bag for the first time in a while, I have a Nikkor 200 mm f4, a Nikkor 105 mm f2.5, a Nikk…

* this sensor is for video, your Nikormat cannot do video

* practicality of digital vs analog, people will trade quality for convenience

* with Bayer filter you don't lose exactly 1/2 of resolution, the algoritms employed do a little better than that

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

#80

Post by Domenic_S »

graycat wrote: post #74

So, with all the critical details here about CCD sensors, you expert guys are telling me that I should not rush out and spend $10 K, $20 K, or whatever for the latest Nikon/Canon single lens reflex with a CCD sensor and a bag of lenses and, instead, keep my old Nikon Nikormat with its bag of Nikon lenses? Let's see, opening the bag for the first time in a while, I have a Nikkor 200 mm f4, a Nikkor 105 mm f2.5, a Nikk…

> carrying a serving tray with her hand made Sachertorte mit Schlagobers (whipped cream)?

What am I reading

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