Where does the GP-E1 get its time from?
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Regarding 120 mp sensor, that is a pro type, have you seen that in a camera, Sony could do a 500Mpixel if they want with theres mobile tech and a 24x36mm surface .
Focus now if you have any knowledge of the subject, dont take it as a personal attack, take it as you do not know what you are talking about, and I am not used to the drivel you are writing, meet me on facts
And Jrista, if you are used to that people are listen to you (You have written many posts here on this forum) I am not impressed of your logic, and please keep your messages short and concise. I take it again,
Simply, there are no evidence that Canon have invest any money in a new sensor linje, this is open figures and seen in business stories for shareholders.There are also companies that make money on communicating what competitors are doing or not. A new sensor line cost about 1 billion US dollars or more, a heavy investment which will also be distributed to general public
Something else to keep in mind that Canon does a hell of a lot more than just DSLR's. They have dozens?, many dozens? (hundreds?), of research groups researching technolgoies for a variety of fields. A lot of it is sensor and lens related for other industries than DSLR, some of it is printer related, there is obviously a lot of optics research, etc. R&D budget slashing in general could affect any one of a number of areas at Canon that has nothing to do with their DSLR camera initiatives.
@Mikael: You stated, more than once, that Canon doesn't have the technology to generate large sensors with small transistors. I beg to differ. They developed a 120mp APS-C sensor with a high readout rate a couple of years ago. I found a page describing it: http://www.canon.com/technology/approach/special/cmos.html.
Their CMOS technology, which is capable of producing larger sized sensors (at least up to APS-H size, but if they can do APS-H size they can do FF size) with pixel sizes as small as 2.2 microns. Their 120mp APS-H sensor sported some kind of hyper-parallel sensor readout and processing to support the 9.5 FPS readout rate. That indicates some kind of column-parallel or maybe row-parallel read and ADC strategy, as the reason Sony designed CP-ADC originally was not so much for the IQ improvement as it was for the readout rate improvement (although in Sony's case they were aiming for 60fps readout for mirrorless cameras.)
I garner two things from Canon's prototypical 120mp APS-C sensor. One, they are most certainly capable of fabricating large sensors with very small transistors (the pixel size is 2.2 microns, so transistor size has to be incredibly small to pack enough red and amplifier circuitry into each pixel). Two, they already seem to have technology that allows very fast hyper-parallel readout of an incredibly pixel-dense sensor. Three, their parallel readout seems to process pixels as well as simply read them, indicating some kind of on-die ADC.
my good you are a really Canon fan boy, do you listen to others or is it only to your own voice, give me one proof of investments from Canon regarding new sensors lines , who are you, and please keep your messages short and not a lot of chatter
As for your presumption that Canon is incapable of developing a new fab or producing complex sensors at 180nm, there is nothing to stop Canon from innovating.
The unfortunate thing is that some website claims they looked over Canon's books and see no sign of the sort of expenditure that hints that they have done this and one Canon employee says they just slashed R&D development.
QuoteThats what competition does in a free market...it spurs innovation. Right now all we have about Canon's next cameras is rumor and speculation, but usually those rumors contain nuggets of factual, if not 100% accurate, insight. Based on the current rumors, I speculate that Canon IS innovating, and developing ways to improve their sensor technology beyond the current limitations it experiences today.
I sure hope so. I'd almost think they'd have to be. But then again I was sure the 5D3 would show low ISO improvements too and again some websites say looking over the books they don't necessarily see positive signs, at least not in terms of new fab lines, but I have no idea how well the website really looked things over or if Canon has some other way. But you would think they'd have to wake up to it all at some point.
QuoteYour missing my point. IF <-- key word here -- Canon can reduce their ISO 100 read noise to the minimums recently seen in their cameras (1.5e- worth in the 1D IV sensor), they then could achieve an improvement in total DR at ISO 100. Sony Exmor effectively normalized read noise across all ISO settings. DXO's measurements seem a little sloppy...I've seen measurements from other reviewers that have much more consistent results, so my guess is that the D800 has a consistent 2.7e- read noise at all ISO settings (effectively the minimum read noise at all ISO settings.) IF Canon CAN DO THE SAME THING....make their minimum read noise from the highest ISO the read noise for all ISO's, like Sony did with Exmor, then Canon would have lower read noise than a D800. If that hypothetical (another key word there...my previous post was hypothesizing...might do you good to learn the difference between a hypothetical argument, which is all we can really do when speculating about future improvements Canon might add to their sensors)...if that hypothetical improvement was made, Canon could improve DR in a future 7D by 2.7 stops.
As for your presumption that Canon is incapable of developing a new fab or producing complex sensors at 180nm, there is nothing to stop Canon from innovating. Thats what competition does in a free market...it spurs innovation. Right now all we have about Canon's next cameras is rumor and speculation, but usually those rumors contain nuggets of factual, if not 100% accurate, insight. Based on the current rumors, I speculate that Canon IS innovating, and developing ways to improve their sensor technology beyond the current limitations it experiences today. That does not necessarily require a reduction in transistor size to accomplish. For that matter, does Sony even have a significant lead in transistor size over Canon? I know they use copper wiring in many of their latest CMOS sensor designs which saves them some space, but I hadn't heard that they generally had significant transistor size savings over Canon.
You are a true optimist, sony exmors advantage is the short analog signal path way to digitization= ADC in the end of every single raw at the sensor edge to hold down the read noise. Canon has nothing alike and do not have the equipment or expertise to do the same.
Yes Sony has a lead to shrink electronics from their mobile camera sensor research and manufacturing.
Time will tell what Canon can do or not, and they must do something about their sensors dynamic range when it is almost the same as in 2004
I don't necessarily disagree, however I think your starting to conflate contexts. I was trying to discuss DR in terms of a digitized image in the context of scaling, which I think narrows the scope and does simplify things a bit. Your now talking about DR in a much larger context, that of the sensor. That moves us out of the realm of the digital and into the realm of the analog, and I fully agree: Dynamic range in the analog realm of a sensor is an entirely different beast, and a much more complex discussion. But...we were originally talking about the dynamic range gained by the act of downscaling a high resolution image. In that context, I don't believe we can "interchange" the dynamic range gained by normalizing read noise...which always exists in the lower levels of a digital image...with highlights. You would always be gaining on the shadow end when you normalize and average read noise, however I think we've both demonstrated that gain is small, even though it can be called a "full stops worth".
A stop of dynamic range in the shadows is interchangeable with a stop of dynamic range in the highlights because you can always meter differently (e.g. underexpose by a stop)
You went off on a bit of a tangent suggesting that the extra dynamic range does substantially not increase the number of "levels" of luminance available, and I showed that it actually does (more precisely, that if I reduce noise by a factor of two, I get twice as many luminance levels). I also showed that by downsampling you can interchange spatial resolution for both dynamic range and number of luminance levels.
So the analysis where you try to demonstrate that the difference is "small" by using that table is incorrect. It's incorrect because when you add noise, you don't just lose the "bottom stop(s)" on the table (for example, levels 1-15) and keep all the others, you're really losing information content in the low order bit(s). You're not eating away at the "bottom of the table", you're eating away at the low order bits.
QuoteI'm still adamant that the D800 sensor is only capable of what its capable of...which by all indications, including DXO's, is about 13.2 stops.
Yes, that's 13.2 stops per pixel. I'm not sure why this matters so much -- the Canon also drops (by about .8 EV) when you go from print to screen because the two cameras don't differ that much in megapixel count. Depending on whether you use DxO's "screen" or "print" number, the Nikon leads by 2.2Ev or 2.5Ev. I'm not sure why you think those 0.3 Ev matter a whole lot -- either way, the Nikon sensor trounces the Canon, so why devote so much effort to trying to prove that the Nikon is "only" 2.2Ev better ?
Back to your #95, the D800 user could underexpose by 1.2 stops. If he downsamples to 8mpx, he will be able to recover those shadows, and get 14.4 stops of dynamic range. I agree that he can't get 14.4 stops per pixel at full resolution.
As long as the destination for the image is some fixed size (print or on screen) and not a 100% crop, the "print" benchmark is the one you should care about. So I don't agree for example with the notion that medium format, full frame and crop cameras are equal in terms of dynamic range even if they are on a per pixel basis.
Would it be too much to ask that this beast ship with built in Wi-fi and GPS?
Thanks Jrista! Although, i admit i haven't understood everything you've said (and there's a lot of it!).
I think we've digressed a long way from what your very first post was trying to say. I've never played with a Nikon but i completely agree with you on the Canon's highlight recovery part (from my far less technical experience in recovering highlights).
If one is interested in the technology aspects of photography it doesn't make him/her any less a photographer than he/she already is (however good/bad that person is!)
Do you people actually take pictures or do you just sit around and analyze the camera and data all day long? Reading all of this gave me a headache and I had to GO OUTSIDE and take pictures!
When talking about DR on a sensor, I agree, its not the same thing as levels (since were talking about an analog signal). But if were talking about downscaling a D800 image and gaining dynamic range, everything is about levels of luminance.
In my original example I simply defined noise in the context of a digitized image as being 3 levels. If we downsample an image and average noise by two fold, then the number of levels that constitute noise is between 1 and 2, and may vary a bit by pixel. I am not sure where your example of "previously, we could only resolve 800, 806, 812...now we can resolve 800, 803, 806, 809" is accurate in the context of downscaling an image. Were not talking about resolving anything here, were talking about a three-component pixel with a 0-16384 level range each, and there is nothing preventing us from using every single one of those levels. The thing that diminishes our post-digitization DR is noise, and averaging it by downscaling...as you described, reduces our noise from 3 levels to 1.5 levels. It doesn't change our ability to have digitized (post-ADC) pixels at any and every level between 800 and 812, it simply adds the ability to have levels between 1 or 2 and 3.
Yes, its a stops worth of improvement, but its not a hugely significant improvement.
It is what it is -- a 1 stop improvement in dynamic range. As we agreed, dynamic range is log2(saturation point) - log2(noise level).
I'd also point out that because you can either set exposure or use a different gray point, an extra stop in the shadows is interchangeable with an extra stop in the highlights -- you can always expose by a stop lower. So worrying about whether you gain a stop in the shadows or highlights is a bit off base. Dynamic range is dynamic range, number of levels is a different beast ...
Now regarding the number of levels -- your ADC could have every level between 800 and 812, but that doesn't mean that you have that many distinct levels. At some point, if the noise is large enough, the number of "levels" you have doesn't matter. For example, suppose you start with 16384 levels. Suppose you add two low order bits and randomly assign them. I think we agree that after adding those bits we don't really have 65536 (16384 * 2 *2 ) "levels" even if we "used" that many. Back to the example we were discussing, if we have a 14 bit ADC and our noise level is 3, the lowest order bit is close to random.
The number of levels we have is the number of levels divided by the number of noise levels (assuming read noise doesn't change across the dynamic range) -- it's essentially exp(dynamic range) * some constant
By the way, when we pool multiple pixels, we don't just have possible 16384 levels any more -- we have 16384 multiplied by the number of pixels (we get multiples of .25 when we average. Or if you don't like fractions, you can just add the pixel values. Either way, you end up with 65536 distinct levels). Of course because of the above this doesn't mean that we can distinguish between all of them.QuoteIf read noise is a whole stops worth (image from Exmor sensor), and it eats away from to "bottom", you aren't losing much. If read noise is a few stops (3 to 4) worth (image Canon sensor), you could be losing 7, maybe 15 distinct levels.
This is highly simplified, the conversion from sensor to digital isn't as ideal and linear as this,
I think it's perhaps a bit too simplified. Recall my previous point -- dynamic range at the bottom is interchangeable with dynamic range at the top because you can always underexpose or overexpose.
Now of course if you insist on putting a hard limit on the number of bits available for the signal, you are more likely to suffer quantization loss with a lower dynamic range. For example, if you have 14 bits to represent 12 sops of dynamic range, you get less quantization loss than if you use 14 bits to represent 15 bits of dynamic range. In practice it seems to me that quantization loss (at least in RAW) is not the problem. Also, as I pointed out, if your read noise is (has standard deviation of) 3, you don't "really" have 14 bits worth of distinct levels (the lowest order bit is almost as good as randomly assigned), so you really would get twice as many levels if you could reduce noise by a factor of 2.
Now if you pool multiple pixels you do get more levels. The number of levels you get grows linearly with the number of pixels you pool, but as I pointed out, the noise goes in inverse proportion to sqrt(N), so your true number of levels increases by a factor of sqrt(N). But again, this is different from dynamic rang.e
Canon doesn't necessarily need improve Q.E. to get more DR. The 7D's lowest read noise is also 2.7e-. I've never really understood why, but read noise increases at Canon's lowest two ISO settings. If Canon can achieve the same thing as Sony, where read noise is pretty much constant regardless of ISO setting, then a 7D with a FWC of 20187e- and read noise of 2.7e- would be capable of 12.9 stops of DR. The lowest read noise achieved in a Canon sensor is 1.5e- in the 1D IV sensor. Thats pretty amazing, regardless, to have a read noise that low for any ISO. If Canon could achieve a 1.5e- read noise across the board, the 7D, with the samw FWC of 20187e-, would have 13.7 stops of DR. Technically speaking, with thermoelectric cooling, making 1.5e- the highest read noise wouldn't be implausible...actually quite plausible. You could probably get read noise below that with sub-freezing cooling.
If you ALSO threw in some additional Q.E. (say, more effective microlenses, backillumination, etc.) and raise Q.E. to around 60%, and add additional noise-mitigation circuitry, and throw in a 16-bit ADC Canon could probably get well beyond 14 stops of DR with pixels less than 4 microns in size. But they don't necessarily have to do all of the above to improve their DR by a stop or two. Some efficient active cooling to keep the sensor below room temperature or even below freezing would go a LONG way towards making 1.5e- ISO 100 read noise and 13.7 stop 7D II DR a reality.
Yeah, but we did. We dropped our noise baseline from 3 to 1.5. That's an extra stop in the shadows.
Well, I think this one statement is most significant. Yes, we gained an extra stop in the shadows,
Yes, and that's what dynamic range is, right ? As you defined it, it's log2(saturation level) - log2(noise level), so we did gain a stop of dynamic range. Because you can adjust the exposure, an extra stop in the shadows is interchangeable with an extra stop at the other end.Quotehowever that stop, in terms of luminance levels gained, is insignificant in the larger picture...its 1.5 levels worth, not 6,000+ levels worth.
Number of luminance levels is a different thing to dynamic range. However, as I explained, we not only gain the stop of dynamic range, we gain double the luminance levels.
e.g. whereas previously, we could only resolve 800,806,812, ..., with the reduced noise we can resolve 800,803,806,809 ... ,
so it really is 6000 levels worth.
This thinking that before you had the numbers 1-1024 and after you have 0.5 and 1-1024 which is "one more level" is simplistic and wrong. You actually also get 1.5, 2.5, ... etc. You get these because you can resolve more due to reduced noise. Or, if you like, you push them a stop and you get 1-2048.QuoteIf the D800 camp here is arguing that they are gaining an extra 2.3 stops on the opposite end that I've classically been looking at the problem from, that is an entirely different story, and far more realistic.
(1) dynamic range is different from the number of resolvable luminance levels, and (2) reducing noise does increase both, so the distinction is not as important as you make it out to be.
|Stop||Levels in Stop|
Yeah, but we did. We dropped our noise baseline from 3 to 1.5. That's an extra stop in the shadows.