Canon develops 35 mm full-frame CMOS sensor for video capture • Hacker News Board

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

#91

Post by coldtea » Tue, Mar 05, 2013, 9:44 AM UTC

klodolph wrote: post #52

Gravityloss wrote: post #17

Earlier quoted context omitted.

Too bad the whole camera business wasted a huge amount of resouces over ten years on a stupid tinier and tinier pixels race.

1. Noise increases as pixel size increases. So you can't just make the pixels bigger. 2. The 5 megapixel camera on an iPhone 4 is pretty amazing. I wouldn't call it a waste of resources. 3. Displacing MF from high-end camera manufacturers requires tiny pixels. You can shoot pictures for e.g. magazines on a $2,000 D600 today, but in 2003 you would have needed at least $4,000 MF camera plus a $10,000+ scanner. Yes, thi…

>1. Noise increases as pixel size increases. So you can't just make the pixels bigger.

No, it does not. It also depends on the sensor technology. Newer APS-C 16 and 20 mp cameras have less noise than 3mp APS-C cameras of 10 years ago, even without applying in-camera noise reduction.

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

#92

Post by lutusp » Tue, Mar 05, 2013, 9:45 AM UTC

coldtea wrote: post #89

eksith wrote: post #30

Earlier quoted context omitted.

Holy cow! I just visited arethuza's Wikipedia link below... I read the NASA trivia about the movie on a forum a few years back and it just popped into my memory. I had no idea these were incredibly rare. Yes, the irony him shooting 2001 wasn't lost on me. Without reflections, space is pretty dark (excluding starlight) so I imagine the new Canon lense will see a lot of space use. Provided it can be made sufficienty RA…

> Without reflections, space is pretty dark (excluding starlight) Lots of infrared too, though.

Distant from stars like our sun, the temperature of space is just 2.73 Kelvins. It's pretty easy to work out the temperature for any given location in space -- just add up the effect of any nearby stars, whose radiation decreases as the square of distance, and add the background temperature of space itself, caused by the Big Bang afterglow.

What this means is that, unless you're close to a star, it is very, very cold. Even at Pluto's relatively nearby location, the average temperature is only 33 Kelvins.

http://en.wikipedia.org/wiki/Cosmic_microwave_background_rad...

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

#93

Post by lutusp » Tue, Mar 05, 2013, 10:17 AM UTC

klodolph wrote: post #52

Gravityloss wrote: post #17

Earlier quoted context omitted.

Too bad the whole camera business wasted a huge amount of resouces over ten years on a stupid tinier and tinier pixels race.

1. Noise increases as pixel size increases. So you can't just make the pixels bigger. 2. The 5 megapixel camera on an iPhone 4 is pretty amazing. I wouldn't call it a waste of resources. 3. Displacing MF from high-end camera manufacturers requires tiny pixels. You can shoot pictures for e.g. magazines on a $2,000 D600 today, but in 2003 you would have needed at least $4,000 MF camera plus a $10,000+ scanner. Yes, thi…

> Noise increases as pixel size increases.

No, it's the reverse -- relative to photon collection efficiency, noise decreases as pixel size increases. For a given pixel size, you have various noise sources, and you have the photon collection efficiency of the sensor. As the sensor becomes larger, the photon collection efficiency increases much faster than the noise does.

http://firmitas.org/Sensor.html

Quote: "The size of a pixel directly impacts how much noise an image will have in low light, and in some cases even in daylight. The bigger the pixel is, the lower the noise because more photons can reach a bigger pixel sensor."

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

#94

Post by thenomad » Tue, Mar 05, 2013, 10:23 AM UTC

scarecrowbob wrote: post #51

thenomad wrote: post #40

Earlier quoted context omitted.

As a filmmaker, I'm more impressed by the burning incense. I don't even make live-action video (I do animation), and I STILL desperately want a camera that can do that. I suspect that the results of showing that video to a room full of filmmakers can be summed up in the phrase "Shut up and take my money."

If you're doing stop motion, can't you just do longer exposures? Or is that impractical in a stop-motion workflow?

To the best of my knowledge, there's no reason not to do that - although I don't do stop-motion, I do performance capture.

(The reason I was drooling over the camera wasn't for any particularly practical use - I wouldn't use it day-to-day. I have on occasion done live-action filmmaking, and I know how INCREDIBLY useful uber-low-light performance like that would be. Seeing the potential for mood and Dogme-style shooting makes me want to pick up a Real Camera again ;) )

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

#95

Post by baq » Tue, Mar 05, 2013, 10:52 PM UTC

Sharlin wrote: post #71

baq wrote: post #54

Earlier quoted context omitted.

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.

suddenly everything started to make sense...

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

#96

Post by prof_hobart » Tue, Mar 05, 2013, 11:44 PM UTC

klodolph wrote: post #78

prof_hobart wrote: post #73

Earlier quoted context omitted.

>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 s…

>You might be surprised at the quality of some of the P&S lenses.

As I have owned several P&S cameras, and done plenty of test shots with them (including in controlled conditions, on tripods in good light etc - despite this not being how the average user is taking the vast majority of their photos), I would not be surprised by the quality of most of them at all. They simply aren't good enough to take a great deal of advantage of much about about 5MP. Yes, you can get ones with pretty good lenses on. But that's far from the norm - and the norm has for years been to fit high megapixel sensors on cameras than can simply not do them justice. Which was the point of my comment.

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

#97

Post by Gravityloss » Wed, Mar 06, 2013, 11:50 PM UTC

klodolph wrote: post #78

prof_hobart wrote: post #73

Earlier quoted context omitted.

>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 s…

The RX100 ain't a point and shoot camera though, it costs more than entry level system cameras, 600 €.

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

#98

Post by Gravityloss » Wed, Mar 06, 2013, 11:57 PM UTC

ScottBurson wrote: post #60

quantumstate wrote: post #44

Earlier quoted context omitted.

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.

No, smaller pixels have more noise (on a pixel basis) because the incoming photons are averaged over a smaller area. Of course, if you have more resolution, you can reduce the resolution in post-processing, and that will also reduce the noise. But then you might as well have used larger pixels to start with. So I think the right strategy is, figure out how much resolution you need and how large a sensor you can affor…

It would make sense to always process the higher resolution image with denoising and demosaicing algorithms and then save that with a much lower resolution as there is less and less information the lower photon counts you use per pixel.

Otherwise you're just saving noise.

Probably if you did a study from people's online photo albums where they just upload originals without thinking, you'd discover that something like 90% of space is wasted on pure noise. Things like the sky or a smooth constant color area that can not be compressed by the jpg algorithm since it is filled with high frequency noise. (Often of the color variety no less.)

There are limits to sensor efficiency. Photon noise statistics gets worse with smaller absolute aperture lenses (focal length times f-number) and smaller field of view (zoom).