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Messages - David Hull

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1
Canon General / Re: Dragonfly, Powered by Canon Lenses
« on: July 12, 2014, 11:22:25 AM »
It achieves this using ten, commercially available Canon 400mm lenses with unprecedented nano-fabricated coatings with sub-wavelength structure on optical glasses.

I only count 8.
It looks like it could hold 10.  Maybe the other two are back-ordered at B&H or had to go back to Irvine for adjustment ;-)

2
Microsoft Lawyer:  Hey Canon, we (Microsoft) have 500,673 active patents.  We're pretty sure you are in violation of several of them.  Why don't you consider taking out a licensing agreement with us.  In return you get access to all our patents and we'll never bother you again.

Canon Lawyer: What if we don't?

MSFT Lawyer:  We begin Litigation proceedings on Monday.

Canon Lawyer:  Well, OK, where do we send the check.




3
It's a CR3 about the fact that the NDA/embargo will expire. That's really it. I wouldn't call this a CR3 about the 7D "replacement" (cleverly worded ;)) itself. Don't get your hopes up too much...all this is is reporting the fact that Canon will be lifting NDAs and allow people to speak freely about certain upcoming products starting in Sept., however we still don't know what those products are. Just that it's the 7D "replacement"...whatever that is...7D II? 3D? 4D? 2D? Something still APS-C? Something maybe APS-H? Something with 10fps? Something with more FPS? It's all still the same old questions...we still don't know anything. We just know now that we WILL know more clearly, but possibly still not for sure, in a few more months. :P
What do you mean it isn't going to be a 7D replacement?  He's got a picture of it right there in the article! ;-)

4
Third Party Manufacturers / Re: D810!!!
« on: June 26, 2014, 12:49:14 AM »
Seems like the 5D iii just got pooped on.  For anyone who can stomach 36MP that is.

Luckily for Canon they have the better lens line-up.  Which is what really matters.
I thought that the 5DIII got "pooped on" by the D800?  Is this new "poop" then?

5
Lenses / Re: Why do fast primes not have IS?
« on: June 24, 2014, 10:33:17 AM »
I'm wondering why fast primes like a 35/1.4 or a 85/1.2 don't come with IS. The fastest lens to feature IS is the 35mm (and the 200mm) f2. Why is that?  :o People would love a 50mm f1.2 IS  ::) Is there some sort of technical problem? I can't imagine anything else, it would sell well, would set them apart, isn't too expensive... Can someone help me?  :)

Hi tayassu!

I will try to make an approach, as far as I can handle your question:
IS (Canon) is a moving optical element inside the lens.
http://en.wikipedia.org/wiki/Image_stabilization
To work properly it has to move fast and accurate. To be fast it has to be of low weight.

Fast apertures need a larger image circle over the whole optics compared to narrow apertures.
Therefore the optical elements of the IS should be larger as well. This leads to higher weight which causes loss of speed and higher energy consumption and also to higher prices because of the more expensive optics.
So with IS Canon always compromises between functionality of the IS and useful max. aperture.

This is my conclusion. Maybe someone else can do better.

I also think that there is a degradation that comes with thee things and the companies that are making fast primes are generally going for the best MTF curve they can get.  So putting the IS gizmo in there costs them some performance in that regard.  Zooms are always a compromise so for those it doesn't matter as much (and they are already big and heavy).

6
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 05, 2014, 10:44:59 AM »
I am not proposing that they test the sensor and ADC separately, they could not do that without opening the box and connecting equipment and that we would really be difficult in the case of Sony.  What I am saying is that they are not really reporting sensor performance, they are reporting camera performance and should say so.

Please don't even suggest such an appallingly horrible possibility!!   :o

"Camera performance" includes evaluation of such things as autofocus, frame rate, buffer depth, shutter lag, viewfinder characteristics, build quality, etc.   How good is an image with low noise and high DR if it's blurry from poor AF or misses peak action due to shutter lag?  No, DxOMark is NOT reporting camera performance.  Not even close.

I get what you're saying – they are measuring the final output of the sensor, on- and off-die amplifier circuitry, the ADC, heat dissipation capacity, firmware coding, etc.  More than just the CMOS chip, but while dissecting the component contributions and characteristics is of academic interest, I'm not convinced it has any practical relevance.  If you ignore their Biased Scores, DxOMark's 'sensor' measurements are useful as one aspect of camera performance to be considered when comparing bodies.
That's what I was getting at.  It is really the whole chain they are analyzing not just the sensor.  If Canon could figure out a way to get some low speed column conversion going on their sensors they would have a pretty high performance solution and we would all have to find something else to whine about :-)

7
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 05, 2014, 10:39:39 AM »
I guess it really depends on how we define class leading. Canon is an international business, it's not there to appease techhie geeks, but to provide it's share holders with a reasonable return on their investment. So if we look at the market, the Canon 5DII and 5DIII are big sellers for Canon. But the Nikon D800 isn't shifting any where near as many units. So, which camera is the more commercially viable? If you really feel that the Exmor sensor is more important to you than your current Canon one, then feel free and jump ship. It's the only metric Canon is really concearned with. If enough people buy a D800 and not a 5DIII then it will cause Canon to listen. In the mean time, Canon's market placement has been skillfully played out and the 5DIII is a brilliant product. The only way to get Canon to loose faith in their market research and placement is to show them it's wrong at a sales level.
I agree completely.  This just doesn't seem to be tipping the scale that much for whatever reason.  That has to be somewhat frustrating for the DxO geeks among us.

8
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 05, 2014, 12:10:46 AM »
I think that DxO does the photographic world a great disservice by claiming to test sensors when they actually test the entire chain.  Lots of folks get very confused.

The disservice done by DxO is in the reduction of their measurements to Scores which are biased and determined in an undisclosed manner. 

What good would it do to test the sensor and ADC separately?  If the sensor is good and the ADC is poor, it's not as if I can just pop a better ADC into my camera.  Testing anything but the 'entire chain' would have no real-world utility (except fueling speculation about what might or might not be possible at some unspecified future time).
I am not proposing that they test the sensor and ADC separately, they could not do that without opening the box and connecting equipment and that we would really be difficult in the case of Sony.  What I am saying is that they are not really reporting sensor performance, they are reporting camera performance and should say so.

The title of this thread "Can Canon deliver a sensor that is truly class leading" is ample proof that a problem exists with people's understanding of this matter.  Once you take the time to figure out how the cameras work and take the time and study the DxO data (particularly as digested by sensorgen), It becomes quite clear what is going on.  What it all says is that Canon's sensor implementation is performing just as well as Sony's it is just that the camera implementation that they chose (and for some reason seem to be sticking with) does not perform as well in this one particular parameter.

I think that we can all agree that the end of the day, photographers take pictures with cameras and not "sensors" and Sony has managed to get 14 bits of DR out of a 14 to 15 bit sensor while Canon has only managed to squeak 12.5 out of theirs.  But it still appears to be a sensor that is quiet enough to produce over 14 bits of DR.  So IMO, to say that Canon's sensor itself is sub standard is simply not true, and the measurements (even those of DxO do not support that statement).

BTW: you are spot on WRT your other comment about DxO's summary scores -- a total crock of crap IMO.

 

9
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 04, 2014, 03:59:24 PM »
...
Who says?  FWIW I don't believe that the flat spot has anything to do with the sensor at all -- it is due to the noise being dominated by that of the ADC which follows the sensor in the Canon designs.  If you really dig into things you will find that the Canon sensors are actually the class leaders in terms of dynamic range, they just foul it up in terms of their system architecture.  The answer to the question "can Canon deliver a class leading sensor" is yes... they already do.  Take a look at the data from Sensorgen for the 5DIII for example:  Min read noise 2.4e-, FWC=67531 for a DR of 14.7 stops.

And Nikon's D4 would whip everything from Canon quite nicely then.

Quote
If they were to put an ADC on-chip similar to what Sony does, they would have equivalent performance maybe even better.

What Canon needs is a "class leading" system architecture and ADC.  This is a nit, I know but it is important because Canon DOES have class leading sensors and has had them for quite some time.

If you mean "system architecture" to mean "sensor architecture", then yes because the ADC is an integral part of the sensor.
When I say system architecture, I mean exactly that -- how the system is architected.  In Sony's case they have optimized the architecture to minimize pattern noise and overall system read noise -- it is an excellent design in that respect.  They achieved this through the use of a distributed ADC structure that they were able to implement on-chip.  It is a clever and innovative approach (originally invented by IBM, BTW).   

Canon has chosen to design their system in am more traditional way using an ADC off-chip.  This has consequences, since it requires a higher speed, more complex pipelined ADC which will not yield the same effective number of bits (ENOB) of the Sony approach.

This is a classic study in system architecture where you can design two radio receivers using the same high performance front end LNA (low noise amplifier) but without optimizing your noise lineup for DR one doesn't work as well as the other.  In this case it isn't a satellite receiver but a camera but the principles are the same.

FWIW, the ADC that canon is using is state of the art, they have a 14 bit converter that is probably getting about 12.5 ENOB at 40 MSPS.  That is about as good as it gets for a pipelined ADC running that fast.  Both companies have state of the art sensors which appear to yield pretty much the same performance, Sony has done a better job on system design by optimizing the system noise line up for this one particular parameter.

If you are going to talk about sensors you need to talk about sensors, the sensor is only one part of the overall system and it is this overall system implementation that determines the noise figure and dynamic range of the camera.  In the case of Canon the sensor and ADC are separate chips.

Aah! That's a breath of fresh air! Thanks for the post! :D
Yea... I think that DxO does the photographic world a great disservice by claiming to test sensors when they actually test the entire chain.  Lots of folks get very confused.  I don't know why they don't take it to the finish line and do what Bob did at Sensorgen and bring it back to the actual sensor performance.  Maybe they don't feel good about posting a result based on an indirect measurement.

Incidentally if the ADC is actually on-board the DiGiC, that would explain a lot since they probably pick up a lot of analog noise bringing the analog signals from the sensor assembly down to the mainboard.  I thought that they had an actual ADC chip right on the back of the sensor subassembly.  Seems to me I have seen it that way in some of the teardowns.

10
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 04, 2014, 10:53:41 AM »
...
Who says?  FWIW I don't believe that the flat spot has anything to do with the sensor at all -- it is due to the noise being dominated by that of the ADC which follows the sensor in the Canon designs.  If you really dig into things you will find that the Canon sensors are actually the class leaders in terms of dynamic range, they just foul it up in terms of their system architecture.  The answer to the question "can Canon deliver a class leading sensor" is yes... they already do.  Take a look at the data from Sensorgen for the 5DIII for example:  Min read noise 2.4e-, FWC=67531 for a DR of 14.7 stops.

And Nikon's D4 would whip everything from Canon quite nicely then.

Quote
If they were to put an ADC on-chip similar to what Sony does, they would have equivalent performance maybe even better.

What Canon needs is a "class leading" system architecture and ADC.  This is a nit, I know but it is important because Canon DOES have class leading sensors and has had them for quite some time.

If you mean "system architecture" to mean "sensor architecture", then yes because the ADC is an integral part of the sensor.
When I say system architecture, I mean exactly that -- how the system is architected.  In Sony's case they have optimized the architecture to minimize pattern noise and overall system read noise -- it is an excellent design in that respect.  They achieved this through the use of a distributed ADC structure that they were able to implement on-chip.  It is a clever and innovative approach (originally invented by IBM, BTW).   

Canon has chosen to design their system in am more traditional way using an ADC off-chip.  This has consequences, since it requires a higher speed, more complex pipelined ADC which will not yield the same effective number of bits (ENOB) of the Sony approach.

This is a classic study in system architecture where you can design two radio receivers using the same high performance front end LNA (low noise amplifier) but without optimizing your noise lineup for DR one doesn't work as well as the other.  In this case it isn't a satellite receiver but a camera but the principles are the same.

FWIW, the ADC that canon is using is state of the art, they have a 14 bit converter that is probably getting about 12.5 ENOB at 40 MSPS.  That is about as good as it gets for a pipelined ADC running that fast.  Both companies have state of the art sensors which appear to yield pretty much the same performance, Sony has done a better job on system design by optimizing the system noise line up for this one particular parameter.

If you are going to talk about sensors you need to talk about sensors, the sensor is only one part of the overall system and it is this overall system implementation that determines the noise figure and dynamic range of the camera.  In the case of Canon the sensor and ADC are separate chips.

11
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 03, 2014, 07:49:01 PM »
And if Canon can do that, can it finally deliver a FF sensor that is also class leading? By class leading, I'm referring to noise control and DR


Canon already has a class-leading sensor, it's in the 6d: nearly zero (esp. vertical) banding (better than 1dx @iso100) means almost the full theoretical dr is actually usable. It has good dr @base iso (boosted +1/3ev by ML and =15ev with dual_iso) and superior dynamic range at high iso: http://sensorgen.info/CanonEOS_6D.html


This is not true. The 6D does NOT have the "full theoretical DR", not even close. The 6D has the same problem as every other Canon camera: A flattened DR curve at low ISO. Canon's DR tops out at around 12 stops of DR. Their sensors are more than capable of more than that, according to Roger Clark the sensor itself is actually probably capable of a little over 15 stops of DR natively (in analog space, before digitization), however the ADC bit depth limits it to 14, and downstream electronics (namely the ADC) introduce so much noise that it flattens the curve, rather than leaving it in it's linear state. It doesn't matter if the 6D ISO 100 noise doesn't have banding...the problem is that it still has a ton of noise. It has 26.8e- worth of read noise, which while less than the 1DX's 38.2e-, it also has a lower FWC, so it's dynamic range is roughly the same.

The problem isn't the sensor. Canon's sensors are very good. Canon's problem is their high frequency off-die ADC units housed in the DIGIC chips. They are just plain noisy.

Roger Clark has evaluated a lot of Canon sensors. His work finds the lowest noise level in the sensor itself, which would be intrinsic sensor noise, devoid of actual read noise. That's dark current noise in the sensor, along with whatever noise the per-pixel amplifiers might introduce. In Canon sensors, that noise level is around 2e-. In the case of the 6D, the sensor's analog dynamic range would be 20log(76606/2) dB, or 91.65 dB, which in terms of stops is 15.27. In the case of the 1D X, which also has ~2e- intrinsic sensor noise, the maximum possible dynamic range would be 93.1 dB or 15.52 stops. These levels aren't realizable due to the amount of read noise at ISO 100. If Canon can get their read noise under control, and get their ISO 100 noise levels down to 3-4e-, their dynamic range would be ~14-14.5 stops. Throw in a little bit of quantization error and PRNU and a 14-bit ADC, and Canon's DR jumps up to the level of Sony Exmors. Throw in a 16-bit ADC, and Canon should be able to achieve 14.5 stops of DR pretty easily. If they can lower their read noise levels even more, they could achieve well more than 15 stops of DR.

Their SENSORS are capable. The rest of their electronics are not. Canon's biggest problem is their approach of offloading the ADC into the DIGIC chip, and running them at very high frequency. Plus, their use of a downstream secondary amplifier doesn't help, but that only kicks in at higher ISO as far as I am aware.


Yep.... someone actually "gets it".  It just blows me away that so many don't really understand what that curve really says with regard to the system implementation. I didn't get to your post before I stuck mine on further down.  I bet Sony looses a bit of performance by running all of that digital crapola in the same die with the sensor stuff -- I suspect their sensor is probably as good as Canon's.

12
EOS Bodies / Re: Can Canon deliver a FF sensor that is class leading?
« on: June 03, 2014, 07:39:40 PM »
Whilst we're going to have to wait a month to find out what the distortion is like on the 16-35/f4L, the MTF graphs and samples tend to suggest it is going to be a class leading lens. And how long have we had to wait for it?!

And if Canon can do that, can it finally deliver a FF sensor that is also class leading? By class leading, I'm referring to noise control and DR that is close to linear right through the ISO range and that matches or exceeds that of Sony sensors.

What's important about it being linear? At the moment Canon sensors have a DR function that is flat in the low ISO range as opposed to Sony's which is linear: below ISO 200 (or is it 400?) there is very little gain in DR from Canon sensors whereas Sony's deliver substantial gains the lower the ISO goes. I suspect that prior to Sony's sensors coming out, people thought that the "flat area" at the start of Canon's graphs looked good because there was no degradation. What people didn't realise is that there shouldn't be any flat spots, rather the DR (colour, noise, etc) response of the sensor should be close to having a linear relationship with ISO.

Who says?  FWIW I don't believe that the flat spot has anything to do with the sensor at all -- it is due to the noise being dominated by that of the ADC which follows the sensor in the Canon designs.  If you really dig into things you will find that the Canon sensors are actually the class leaders in terms of dynamic range, they just foul it up in terms of their system architecture.  The answer to the question "can Canon deliver a class leading sensor" is yes... they already do.  Take a look at the data from Sensorgen for the 5DIII for example:  Min read noise 2.4e-, FWC=67531 for a DR of 14.7 stops.

If they were to put an ADC on-chip similar to what Sony does, they would have equivalent performance maybe even better.

What Canon needs is a "class leading" system architecture and ADC.  This is a nit, I know but it is important because Canon DOES have class leading sensors and has had them for quite some time.

13
can anyone explaine why Canon has no high Mp FF camera as Nikon
Brett
Can you explain why the 5DIII seems to outsell the D800? Just curious.

14
I've waited a long time for Nikon to recapture the lead on Nikon and their 36 mp camera. And now I read that Nikon will introduce an upgrade to the 800e in June.  Why am I not jumping ship?  I do have a lot of canon glass and have been a local customer. I own the mk III and 6d and I love the images .BUTT, COME ON ALREADY cCanon. Get your stuff together!
The thing I wonder about your post and others like it is - how many people "need" 36+ MP?  Sure, it's always nice to have more than you need, but unless you have the very best lenses - Canon Mk II big whites, Zeiss Otus 55 & Zeiss 135 f/2, etc., there will be little increase in actual resolution.  It would help a lot with cropping and would equalize the FF vs. crop war for wildlife...but again, only with the very best lenses and technique.  I've printed many large prints at 40x60 or larger at 300dpi (that's around a 3x enlargement for 5DII files) and found little to complain about.  Most people share photos at 1600x1200 or less online and rarely, if ever, print anything over 8x12"...but these are the people who often scream the loudest over their inadequate megapixel bodies!

While we wait for more MP, I'll keep shooting what I've got and won't lose any sleep over my 18 and 22 MP bodies 8)

They "need" it because Nikon has it and Canon doesn't.

15
Pricewatch Deals / Re: Deal: EOS 5D Mark III Body $2574
« on: May 11, 2014, 03:38:56 PM »
Just out of curiosity, are there similar deals around for the D800?  I don't shoot Nikon so I don't follow them but I an curious if these sorts of deals on Nikon gear pop up every now and again.

I've seen Newegg selling the D800 for around $2100, so yes, there are deals.
 
The problem with a D800 is the lenses.  Only a few match the high MP sensor, and they have horrible CA, so you have to work on them a lot.
 
I use live view, and that really did not work well on my D800, so if you are a liveview user, think twice.
 
At ISO 200 in high contrast outdoor lighting, it can be truly amazing.  For low light ISO 12800 indoor shots, its amazing as well, but not in a good way.
No, I am not considering one, I was just curious if there were similar deals on the equivalent Nikon gear -- looks like there are.

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