August 30, 2014, 04:19:00 PM

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Messages - pierlux

Pages: [1] 2 3 ... 8
1
EOS Bodies / Re: EOS 7D Mark II & Photokina
« on: August 29, 2014, 07:30:21 PM »
Lee Jay, jrista, and also sarangiman , sorry for the delay, but my ex-wife lives 40 km away from me so it took me a while. Plus, I'm very slow in writing.

Thank you guys for the effort spent in replying, you almost convinced me.  I think I have to re-read your replies another couple of times to fully understand all, but I'm nearly convinced. I have a couple of questions. I still don't get what
...the 2.04 micron pixels of the S3IS provide better IQ behind the same lens as the 8.2 micron pixels of the 5D.
actually means. Problem is, comparing sensors having different resolution, we are far from "all the other conditions being equal" here. Are you sure those images are ISO 800? My old 6 MP 300D at 800 ISO is noisy as hell, and it's APS-C. The fact is that I still have problems in regarding normalization as a fair mean of comparison.

Moreover, I still think the following logic is flawed. jrista, you say
Your only thinking about the individual pizza slices here. Your missing the bigger picture: The eater who eats 1/6th of a pizza eats 1/6th of a pizza SIX TIMES!! Therefor, the eater is not eating one pizza slice...the eater is eating A WHOLE PIZZA!  ;D This is the critical point that everyone seems to miss. If an eater eats two 15" pizzas, one cut into 6ths and one cut into 8ths...has the eater eaten less total pizza when eating the one cut into 8ths? NOPE!! He's still eaten a whole 15" pizza, same as he did when he ate the one cut into 6ths.
but I still think the eater here is not the whole sensor, it's each individual photosite. If the eater was the whole sensor, you'd obtain zero resolution, no detail. But you need detail to produce a meaningful image, so you must compare the eater to the single photosite. So the more the eaters (the higher the resolution), the less amount of pizza each eater eats.

I know BSI sensors have the wiring on the opposite side, and that large sensor only marginally benefit from this configuration, that's why this more expensive and lower yield technology is not used in larger sensors, but this is true for (relatively) low density photosites per area unit. The higher the density, thus the smaller the photosites, the greater the benefit. I don't know the numbers, but are you sure the wiring of conventional sensors matter so little in the light blocking effect on the photosites? Does a 24 MP APS-C sensor, even at 180 nm, still marginally suffers from the interposed wiring? jrista, it seems you know where to find such information, I'd like to deepen my knowledge, why don't you post the most interesting links you find, every now and then, on CR? I mean not now, don't get me wrong, but you're one of the most active posters here, I'm sure at least some CR members would appreciate some technical reading sometimes, I for sure.

Thank you all guys, it's very late here, good night!

Ah, my son and I had pizza for dinner, irony!

2
EOS Bodies / Re: EOS 7D Mark II & Photokina
« on: August 29, 2014, 04:01:51 PM »
Too many of you claim that a higher MP sensor does not have more noise than a lower MP one, all conditions being equal, and support this claim with mathematics, but that's not true in the real world. Some even claim that smaller photosites have less noise than bigger ones: now, that's the kind of claim that should make all of us invoke Santa, bigfoot and rainbow-pooping unicorns going on vacation together with a flying saucer. The real world behaves differently.

Oh, really.  Same ISO, same f-stop, same shutter speed, same focal length, same subject, same lighting, shot in raw, same raw processing tool.  The pixels on the left are 1/16th as big (in area) as the pixels on the right.



Which ISO? Which f-stop? Which sensors? Could you provide a link, please? I've found this

ISO 800 (the highest setting available at the time on the small pixels.  The cameras as the Canon S3IS and the Canon 5D.

So the 6 MP p&s S3IS has better IQ of the 13 MP full frame 5D? Could you provide a link please so that I can see all by myself without asking you more detail? Thanks. Sorry, but I'm going to board my car in 5 min, as I said I have to pick my son to spend the weekend with him. I promise you I'll publicly apologize if you convince me, but please Lee Jay, read all my post and tell me where my logic is flawed. See you tomorrow (or tonight, I'm on the other side of the world...)
Cheers!

3
EOS Bodies / Re: EOS 7D Mark II & Photokina
« on: August 29, 2014, 03:28:44 PM »
Too many of you claim that a higher MP sensor does not have more noise than a lower MP one, all conditions being equal, and support this claim with mathematics, but that's not true in the real world. Some even claim that smaller photosites have less noise than bigger ones: now, that's the kind of claim that should make all of us invoke Santa, bigfoot and rainbow-pooping unicorns going on vacation together with a flying saucer. The real world behaves differently.

Oh, really.  Same ISO, same f-stop, same shutter speed, same focal length, same subject, same lighting, shot in raw, same raw processing tool.  The pixels on the left are 1/16th as big (in area) as the pixels on the right.



Which ISO? Which f-stop? Which sensors? Could you provide a link, please? I've found this

http://photos.imageevent.com/sipphoto/samplepictures/Pixel%20density%20test%202%20detail%20filtered.jpg

but I can't find the exif, nor a caption. Sorry, I'm not particularly smart with computers... help me. Thanks!

4
EOS Bodies / Re: EOS 7D Mark II & Photokina
« on: August 29, 2014, 03:04:56 PM »
Sorry, it's a long post, maybe too long.

In physics, the Carnot cycle is an ideal representation of a perfect engine having 100% efficency. It is a useful thermodynamic representation to explain energy conversion. In the real world, such a system does not exist.

Too many of you claim that a higher MP sensor does not have more noise than a lower MP one, all conditions being equal, and support this claim with mathematics, but that's not true in the real world. Some even claim that smaller photosites have less noise than bigger ones: now, that's the kind of claim that should make all of us invoke Santa, bigfoot and rainbow-pooping unicorns going on vacation together with a flying saucer. The real world behaves differently.

Saying bigger pixels let more light in is like saying cutting a 15 inch pizza into 6 slices instead of 8 gets you more pizza.

No. Your logic is flawed.

If the pizza represents the sensor, the number of slices correspond to the number of the pizza eaters, represented by the sensels, i.e. photosites, i.e. pixels. An eater who eats 1/6 of the pizza eats more than one eating 1/8 of it. An ideal 24 x 36 mm sensor being a single light sensitive unit is a one pixel sensor which, let's say, collects 1 billion photons at a given time unit and luminous intensity; it has the lowest resolution possible, but it would be capable of letting you know if even a bunch of photons have hit it or not with 100% certainty, i.e. with zero noise. Ideally, if you divide that single huge photosite into 1 million smaller photosites (1 MP sensor), each photosite receives IDEALLY 1000 photons under the same conditions; in the practice it's less than 1000 because of the wiring and the spacing between photosites which equally absorb the photons, but do not convert them into a useful signal, instead convert them into heat, which is detrimental. This 1 MP sensor has sufficient resolution to resolve enough detail for a very small print, and with today's tech you could probably use it at 204,800 ISO or more with very low noise (and before any of you reply that you can reduce the size of the image and therefore reduce noise and equally obtain the print, try exposing a 36 MP sensor at 204,800 ISO or higher if you can...).

Again, the same sensor with 20 MP exposed in the same conditions does not collect 50 photons per photosite, but MUCH LESS this time due to massive wiring and lots of wasted space between photosites, so you have a high resolution image, but with a lot of noise.

Actually, in my example with 1,000,000,000 total photons hitting a 24 x 36 mm sensor I think you'd have only random noise at 20 MP, but it was for the sake of explaining. I'm not talking quantum efficency at all here, it's just the number of photons you can effectively use I'm talking about. Moreover, we don't have a linear relationship between number of photons and noise, so it's not as if you have half of the photons per photosite you double the noise, the situation is worse in the real world.

The Canon 1Dx is 18 MP; in the Nikon D800, being 36 MP, each photosite collects LESS than one half of each of the Canon's photosites, that's why the 1Dx is much better in low light. And the D800 holds because of its superior sensor tech (let's face it, fortunately Canon's system is better as a whole), otherwise they wouldn't have made it 36 MP in the first place.

In the pizza analogy, the more you cut the pizza, the more breadcrumbs, morsels, atomies you produce, leaving the eaters with less and less pizza to eat to the point that, putting together all the slim slices of pizza eaten by all, they add up to not even a quarter of the original one. And, actually, a pie should be a better fitting analogy.

It's like having a 100 x 100 ft room all for yourself, 10,000 square feet is plenty of space. But if you want to accomodate 100 people inside it and offer them a bit of privacy, you have to build walls which eat space, not to mention furniture, so you end up with much less than 100 sq. ft for each dweller.

Still not convinced? OK, you may say "who are you to stand up and make such claims against my maths?", so let's look at what Canon's engineers have done, I bet they know more than me or anyone else on CR about silicon performance and noise. This is what I wrote in a previous post:

"There's a reason the 1Dx has the best (to my eye) IQ of all the DSLRs available to date (yes, better than any Nikon I think): its 18 MP FF sensor. And there's a reason why Canon developed a prototype sensor with photosites 7.5 times larger than the 1Dx: to capture quality video in candlelight (candledrkness sounds better, though). Don't know if you remember, but check these:

http://www.canon.com/news/2013/mar04e.html

http://petapixel.com/2013/09/13/canon-debuts-exciting-prototype-sensor-exceptional-low-light-capability/

And Sony? Compare the the 36 MP Alpha A7r(esolution) and the 12 MP A7s(ensitivity), then say again that more MP does not mean more noise if you dare. At base ISO maybe, but try going at 800 and beyond...

And should somebody dare claim again that smaller photosites means less noise as I've read too many times, remember Santa & Co. are watching us from their flying saucer... And again, at base ISO maybe, but what's the point of shooting 36 MP and then reduce resolution in post to lower the noise and make small prints or web sized images?

I'm going to spend the weekend with my son, so I'll be having a look at CR every now and then, but I'm not going to post, sorry. Have a nice weekend you all, too!

Peace!


5
EOS Bodies / Re: EOS 7D Mark II & Photokina
« on: August 28, 2014, 08:46:56 AM »
If what we posted turns out not to be true, it will be the greatest hoax of specs that I have seen in the 6 years we’ve been around.

But it could still be 20.2 and be a new improved sensor (not identical), what you've posted still true and for you not to have been hoaxed though, no?

I remember voices from past Canon Rumors claiming different prototypes were around, couldn't it be the leaked specs are a mix of several different "experiments"?...

The good news is that if it is a totally new sensor, it may be much better than the 70d and it will have better high ISO noise at 20.2 than 24 mp. Im all for a smaller sensor in aps-c. Truthfully, I wish it was closer to 12 or 16. We'd have a killer crop camera!

Partly agreed.  As I said in Don Haines' poll thread, either a low res/good high ISO IQ old tech sensor, or a high res/supposedly better high ISO IQ new tech sensor would do for me. I put better high ISO IQ than the 7D on top of the specs in order of importance, otherwise to me it's 70D or 80D.

6
EOS Bodies / Re: Are you planning to purchase a 7D2
« on: August 28, 2014, 06:03:59 AM »
I haven't read this thread yet, just voted and now I'm writing this, I'll post and then read all.

I voted "No, unless it exceeds what is expected", of course meaning what the rumor on the specs says. But I'm going to buy a Canon APS-C camera anyway. Should the sensor, and therefore IQ to some extent, be the same of the 70D (or of the 80D which will probably follow soon), there's no compelling reason for my needs to want more, except maybe weather sealing: 8 fps should be enough, coming from a 5D2 which didn't allow me to shoot birds, wildlife and sports: I'll be a beginner in those departments, I've tried just for fun, but my keeper rate was ridiculous, due also to lack of a proper focal length.

I resolved not to be an early adopter this time and to wait for the price to lower a bit since I also need a longer lens, my longest at present is 300 mm, not enough, and I'm budget limited.

I had great expectations on the 7D replacement as concerns IQ, and also in all the other compartments TBH, but I put IQ on top. Unlike te majority here, I'd gladly sacrifice resolution in order to have a considerable advantage in high ISO IQ over the 7D. Craig says he's "90% confident these are accurate EOS 7D Mark II specifications": I'm hoping that 10% remaining includes sensor specifications and FPS :). Either 15-16 MP with the old sensor tech and a crazy 12-14 FPS, or 20-24 MP with a brand new sensor and 10 FPS: both options would do for me. Otherwise, like I said, it's 70D or 80D.

Reading the thread on the specs was fun, 51 pages, wow! But it was also bittersweet pain and pleasure, I stayed out of that, some of you guys should calm down a bit sometimes.

I'm going to post this and read this thread now, cheers!

And peace!

7
EOS Bodies / Re: Patent: Canon EF 180mm f/3.5 DO Macro
« on: July 29, 2014, 06:10:26 AM »
The 400 and 70-300 DO are 13 and 10 years old, respectively. Moreover, they were the first of their kind to appear as photographic lenses (I think, as far as I recall, were they actually?). So why do we assume the new DO lenses, should they ever hit the shelves, will have the same IQ issues of their predecessors? IMHO, along with a higher price as compared with their non-DO counterparts, if any, they will offer much better IQ than the previous generation of DO lenses.

8
EOS Bodies / Re: EOS 7D Mark II Announcement September 5, 2014?
« on: July 07, 2014, 03:46:01 PM »
 :) ;) :D ;D 8) :P  :-*!!!!!!!!!!!!!!!!

9
EOS Bodies / Re: New Sensor Tech in EOS 7D Mark II [CR2]
« on: June 19, 2014, 12:52:18 PM »
I think CR guy knows more than he's reporting. C'mon Craig, tell us something more!

10
EOS Bodies / Re: Mirror flip speed limit?
« on: June 14, 2014, 01:09:44 PM »
[...achieving a speed equal or even better than the 1Dx in an APS-C-sized DSLR represent a much smaller engeneering effort than that required for FF since the mass of moving parts (mirror and shutter) involved is approx 1/3 of a FF camera, so much less inertia and, consequently, less energy required.
Would anyone familiar with mirror flip physics care to speculate on what the maximum achievable (and durable)frame rate might be?  (Speaking APS-C size mechanics only, disregarding processing speed  ;) )
I would, if I were familiar with maths and physycs, but unfortunately I'm not. Apart from the logical statement that moving a small mass requires less energy than moving a bigger one, I can't produce mathematical evidence of this. But I think the maximum 'achievable' frame rate, disregarding processing speed, could be higher than the maximum 'convenient' (or 'applicative') frame rate since, as you mention yourself, durability kicks in, together with image quality degradation due to vibration. I think a 'theoretical' burst at 25 fps would possibly introduce an unacceptable amount of vibration blur.

11
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 14, 2014, 12:44:12 PM »
do the Magic Guys have to begin again from scratch every time they 'assault' a new model or can the previous work be transferred, in the form of pieces of code or at least expertise, from one camera to another?

No, the basic ML codebase stays the same and is very mature by now - i.e. integrating with Canon DryOS as far as setting props and memory allocation is concerned. The 7d1 has a unique catch though which might also apply to the 7d2: real dual digic-processing (and not just offloading the af to a digic).

That's the reason the 7d1 port didn't get started for some years as it wouldn't boot at all, and even now some features don't work at all. In general, my estimation is one year from "Hello World" on a newer camera to a release which has been tested enough so everything works w/o hiccups. *If* a maintainer for the camera is found, and that's not very likely since it's an unpaid job requiring months of man-work. Btw the 6d is unmaintained right now (but somehow working), and so is the 100d (not working at all).
Thanks a lot!

12
EOS Bodies - For Stills / Re: Mea Culpa! - The World Cup in Brazil
« on: June 13, 2014, 10:24:53 AM »
Pity about Fred's cheating and Neymar dirty play though.
Indeed!
Wonder just how many togs were at that game, the entire pitch seemed to be surrounded by them. How do they all earn a living with such saturation?
Well, it's the FIFA World Cup...   Rather, how do they not intertwist and tangle with each other, clumped and compressed as they are in such a tiny space! Looking at them it seems impossible not to bump and push others as they follow the action.

13
EOS Bodies / Re: re
« on: June 13, 2014, 09:10:21 AM »
...IMO, the most critical thing that absolutely must be present is an appreciable increase in IQ / reduced noise.

...we need better noise performance at reasonable ISO's from 1000+ which is commonly needed for wildlife shooting.

... I will be ecstatic if there is increased IQ / reduced noise.

...If, on top of an IQ increase, they could squeeze a few more MP in, I would not complain.
Welcome to CR! I wholeheartedly agree, and voted 'other'. The only specs that matter to me are related to IQ and FPS, so my wishlist is limited to:

1-2 stops better high ISO performance over the 7D (even at the expense of resolution if necessary), and

12-16 FPS (yes, equal or better than the 1Dx).

Before you label me as heretic, I would like to underline that achieving a speed equal or even better than the 1Dx in an APS-C-sized DSLR represent a much smaller engeneering effort than that required for FF since the mass of moving parts (mirror and shutter) involved is approx 1/3 of a FF camera, so much less inertia and, consequently, less energy required. This is entirely possible, and concern about possibly eating the flagship's sales is BS: I imagine a lot of 1Dx owners buying a 7DII to complement their flagship. Plus, amateurs like me, who cannot afford (or justify) the financial effort for a 1Dx and related big white glass, could finally deal seriously with sports and wildlife for less than half the cost of FF. In addition, should Canon lose a bunch of 1Dx sales, that would be largely compensated by selling other Canon gear in the form of 7DII.

On a side note, the high MP option of APS-C is already here: it's called 70D, and at this point, given the turnover of the xxD line, the 80D is not even so far away after all.

14
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 12, 2014, 02:37:06 PM »
Knowing Canon, they will take great care not to deliver a "mini 1dx" at 1/3 of the price that even works better for wildlife in good light because of the gain in reach.
I hope and fear at the same time that if Canon deliver a true mini 1Dx, it will be priced around 1/2 of the current 1Dx price, which means approx as much as the 5DIII at release date. At this price tag it wouldn't eat away 1Dx sales by much.

Whatever comes, I hope all the hard work carried out by the ML guys on the 7D will be in some way profitable for the 7DII firmware hack, too. You're quite The Expert among CR members on this matter, so please excuse my ignorance, but I'm curous and have to ask: do the Magic Guys have to begin again from scratch every time they 'assault' a new model or can the previous work be transferred, in the form of pieces of code or at least expertise, from one camera to another?

15
EOS Bodies / Re: A Few EOS 7D Mark II Specs [CR1]
« on: June 11, 2014, 02:37:44 PM »
At my own risk, let me add - and let the bashing begin! - that I'd be happy to see fewer and better MP than the 7D along with FPS equal or higher than the 1Dx.

To me, more pixels means better image quality (yes, including noise performance)
At base ISO or low ISO settings yes. At high ISOs, I respectfully disagree. There's a reason the 1Dx has the best (to my eye) IQ of all the DSLRs available to date (yes, better than any Nikon I think): its 18 MP FF sensor. And there's a reason why Canon developed a prototype sensor with photosites 7.5 times larger than the 1Dx: to capture quality video in candlelight (candledrkness sounds better, though). Don't know if you remember, but check these:

http://www.canon.com/news/2013/mar04e.html

http://petapixel.com/2013/09/13/canon-debuts-exciting-prototype-sensor-exceptional-low-light-capability/

Nice thread, too bad I have to quit now, see you later guys!

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