September 02, 2014, 05:30:00 PM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - roguewave

Pages: [1] 2 3 4
1
EOS Bodies / Re: EOS 7D Mark II & Photokina
« on: August 28, 2014, 01:17:45 PM »
I do believe in Santa Claus. I do I do I do.  And flying reindeer.  And rainbow-pooping unicorns.  Any of those are more likely to be real than an APS-C sensor that's as good or better than the 5DIII at high ISO. 

In a fight between physics and fantasy, my money is on physics.   8)

I don't disagree with you about sensors, but still, be careful betting all your money on it :)...

"Heavier than air flying machines are impossible."
   -- Lord Kelvin, president, Royal Society, 1895

"The resistance of air increases as the square of the speed and works as the cube [of speed]....  It is clear that with our present devices there is no hope of aircraft competing for racing speed with either our locomotives or automobiles."
   -- William H. Pickering, Director, Harvard College Observatory, 1910

"Even considering the improvements possible...the gas turbine could hardly be considered a feasible application to airplanes because of the difficulties of complying with the stringent weight requirements."
   -- U. S. National Academy Of Science, 1940

"Professor Goddard...does not know the relation of action to re-action, and the need to have something better than a vacuum against which to react....he only seems to lack the knowledge ladled out daily in high schools."
   -- 1920 New York Times editorial on Robert Goddard's rocket work.

"The energy produced by the breaking down of the atom is a very poor kind of thing.  Anyone who expects a source of power from the transformations of these atoms is talking moonshine."
   -- Ernest Rutherford, 1930

"This foolish idea of shooting at the moon is an example of the absurd length to which vicious specialization will carry scientists.  To escape the Earth's gravitation a projectile needs a velocity of 7 miles per second.  The thermal energy at this speed is 15,180 calories [per gram].  Hence the proposition appears to be basically impossible"
  -- A. W. Bickerton, 1926

"Fooling around with alternating currents is just a waste of time. Nobody will use it, ever."
   -- Thomas Edison


2
Your talking about on a per-pixel basis. On a per-pixel basis, that is true. However I'm talking about on a whole-image basis, or as it's called, on a "normalized" basis. When you compare images as a whole at the same size, assuming the same absolute area of sensor was used, then there won't be any difference in noise regardless of pixel size. There will, however, be a difference in detail.

This all assumes same pixel generation. The 5D III does have an advantage in upsampling due to it's newer pixel generation. It has higher quantum efficiency and overall a better pixel architecture, than the 7D pixels. That means less noise per pixel. I actually wish I had a 70D. That would make for a better comparison, as then both cameras would use sensors of similar generation, instead of being separated by over three years of technology. That's unlikely to happen unless I meet someone with a 70D who will let me borrow it for a night, though...as I have no intention of buying a 70D.

Jrista, thank you for the comparison! I found it very interesting.

I believe your experiment also shows that the current Canon FF sensors do not outresolve good lenses - contrary to some claims I've seen on this forum, essentially saying that lenses are the limiting factor and higher resolution FF sensors are pointless.

3
PowerShot / Re: Canon Announces the PowerShot SX520 HS & SX400 HS
« on: July 29, 2014, 10:05:34 AM »
"...ideal for active families that want to take shots of their children’s soccer game..."

and with a 1008mm equivalent at the long end, they can do it without even leaving home :).

4
Lenses / Re: Review: Sigma 50mm f/1.4 DG HSM Art Lens
« on: June 11, 2014, 05:38:04 PM »
What? Their review says nothing about the old one being better.

http://www.popphoto.com/gear/2014/04/lens-test-sigma-50mm-f14-dg-hsm-art-lens

Why, it says:
In terms of our SQF test, the new Sigma beat out the 50mm f/1.4 offerings from Canon, Nikon, Sony and the Sony Zeiss. However the original Sigma 50mm f/1.4 EX lens and the monstrous Zeiss 55mm Otus lens did edge it out, ever so slightly. Oddly enough, the Sigma 50mm f/1.4 EX still holds the title of being our benchmark for 50mm f/1.4’s in this test.

5
...
One of the coolest moments I've ever had in nature, and I won't forget it.  The key was avoiding people at all costs. I had the place to myself because it wasn't deemed "as good" at sunrise.

Or because you were the only one willing to get up in the middle of the night and get to location before sunrise :-). Either way, very nice shot and congrats on the publication!

6
Oh, and guess what?  Sales figures also impact the business decisions being made by whatever brand meets your camera system needs, too.

I think you're flipping the pancake a bit.

Sales do matter in terms of determining the business decisions of a company. We however are the end users, not the company. To us it can be nice to know why they did this or that, but ultimately it is a very academic interest. Sales figures do not affect our experience once the product is in our hands and do not improve our output or our enjoyment. The first rule of statistics is that it never applies to individual cases.

In the end of the day, I don't really care whether Canon feels the need to update this or that. My money is supposed to be spent on fulfilling my needs, not Canon's. If their products are good I buy them, otherwise I don't and it doesn't really matter if other people think they're good for them. If I have to choose, I'd rather be a quality minority than a trivial majority, yes.

...

Absolutely. The explanation that Canon does not update their lenses for > 20 years because the market lets them get away with it is logically correct, but not particularly satisfying for those end users, whose needs aren't completely met.

It's like your kid saying the reason he hasn't been doing his homework is because he can get away with it by copying his friend's solution... a valid explanation, but probably not one you want to hear.

7
Pricewatch Deals / Re: Deal: Canon EF 24-105 f/4L IS $648
« on: December 22, 2013, 09:48:48 PM »
I always get really excited when I see good deals such as this. Then I remember I live in norway :(

Funny :-). Seriously though, aren't there deals in Norway? What's the price over there?

Here in Brazil the 6D can't even be found at stores (just searched -- not even online), but the 60D is worth around US$ 2,000 body-only and up to US$ 3,500 with the 18-200 kit lens. Pretty ridiculous.

Are you serious? That's crazy! For that amount, you could probably fly to the US to buy it, and still have money left after paying airfare and hotel :-).
Exactly, plus you could get a second one and sell it for a reasonable amount when you return back!!

What's the reason for that? Is it Canon's pricing policy? Electronics in general? Or is everything more expensive? I'm guessing something else (i.e. food, housing) must cost less, because it would be hard to get by paying 3x for everything. Unless your incomes in dollar terms are proportionally higher, which is unlikely.

8
Pricewatch Deals / Re: Deal: Canon EF 24-105 f/4L IS $648
« on: December 22, 2013, 08:46:10 PM »
I always get really excited when I see good deals such as this. Then I remember I live in norway :(

Funny :-). Seriously though, aren't there deals in Norway? What's the price over there?

Here in Brazil the 6D can't even be found at stores (just searched -- not even online), but the 60D is worth around US$ 2,000 body-only and up to US$ 3,500 with the 18-200 kit lens. Pretty ridiculous.

Are you serious? That's crazy! For that amount, you could probably fly to the US to buy it, and still have money left after paying airfare and hotel :-).

9
Pricewatch Deals / Re: Deal: Canon EF 24-105 f/4L IS $648
« on: December 22, 2013, 07:33:41 PM »
I always get really excited when I see good deals such as this. Then I remember I live in norway :(

Funny :-). Seriously though, aren't there deals in Norway? What's the price over there?

10
Having seen this setup, now I understand how happy you must be getting the "tiny Canon M"  ;D.

Nice pictures!

11
EOS Bodies / Re: Canon Dual-Scale Column-Parallel ADC Patent
« on: December 20, 2013, 03:57:37 PM »
The patent looks like a ramp ADC - they don't take the electrons out to count them, but use a voltage comparison. The unknown pile of e- on the right, you measure how long you have to add charge on the left side until both are equal(or the known one grows larger then the unknown). In theory nothing stops you from using multiple heaps that grow at different rates. You just have to keep crosstalk, external influences and such under control.

Thank you, I think I got it!

12
EOS Bodies / Re: Canon Dual-Scale Column-Parallel ADC Patent
« on: December 20, 2013, 03:52:06 PM »
I wouldn't call it HDR. HDR is a very misused term as it is. In its proper form, a High Dynamic Range image is an image with an EXCESSIVBLY HIGH dynamic range, stored as 32-bit floating point numbers with extremely fine precision and a dynamic range that could potentially equal thousands of stops (i.e. it can represent numbers from a couple billion down to billionths.)

HDR as it is commonly (mis)used simply refers to the mapping of tones into a limited dynamic range from a source file that might have slightly higher dynamic range. What Canon is doing isn't exactly HDR...it is a specialized read process that will allow them to better utilize the dynamic range they already have access to, but which is otherwise being diminished by read noise.

I didn't mean to call this process HDR in the strict sense - you're right, it is a misused term.

Regardless of the exact meaning, I was thinking of the common understanding of HDR along the lines of:
...HDR compensates for this loss of detail by capturing multiple photographs at different exposure levels and combining them to produce a photograph representative of a broader tonal range... (wikipedia)

I could be wrong, but isn't that the same idea? Creating the equivalent of two different exposures by applying two different gain levels and then combining them. The difference is pushing it onto the sensor rather than post-processing in software, so there is no need to take multiple shots at different exposure.

13
EOS Bodies / Re: Canon Dual-Scale Column-Parallel ADC Patent
« on: December 20, 2013, 03:22:35 PM »
They aren't splitting it. I am not 100% exactly certain what they are doing, but from what I do understand, when a pixel is read, it is amplified twice, and the results of those different amplifications are transferred to the CP-ADC units simultaneously (on different channels). Same source pixel, two separate but full power signals, which are then blended together at conversion time. It is basically the same thing ML did, only with the appropriate dedicated hardware fabricated right into the sensor to do it right.

I assume there is something clever somewhere in the implementation. HDR has been around for a while, even before ML. It's hard to believe nobody thought earlier about pushing the process into the sensor instead of software.

14
EOS Bodies / Re: Canon Dual-Scale Column-Parallel ADC Patent
« on: December 20, 2013, 02:27:08 PM »
I keep wondering what is going to happen in the future with dual-pixel technology. They have the ability to read both sides of the pixel seperately, I wonder how much work it would be to set the two sides to different ISO values, read them both, and combine the values for greatly expanded DR.

This would obviously require more computing power than just reading the sensor would, but comments out of Canon about the greater computational needs of future cameras ties in with this... I am really curious to see what happens with the 7D2..... It should be dual-pixel and dual processor (Digic6 or even 6+????) so it will be able to do a lot more computing than a 70D. The next year or so could be interesting.

They wouldn't need to bother with the dual-pixel approach with this patent. They simply read "the pixel" (regardless of whether it is a single photodiode, or two/four binned, whatever) with two different gain levels (different ISO settings, done simultaneously on different signals). This patent offers a much better way to solve the problem without resorting to "hackish" approaches like what ML did, or like what you suggest with reading one half the pixel at one ISO and the other half at another ISO (which wouldn't be nearly as good, since each half pixel is only getting half the light, so the half-reads would already be at a disadvantage large enough to completely eliminate any gains you might make with the dual-read process in the first place.)

Even better than simply reading half pixels at different ISO settings, this patent reads each pixel twice simultanesously at different gain levels, while also bringing the ADC on-die and column-parallelizing them, allowing them to run at a lower frequency, thus reducing their potential to add downstream noise. With column-parallel ADC, they could do what Sony Exmor does...per-column read tuning to eliminate vertical banding. It also brings in the benefit of shipping image data off the sensor in an error-correctable digital form, eliminating the chance that the data picks up even further noise as it travels along a high frequency bus and through a high frequency DIGIC chip. This patent would single-handedly solve a LOT of Canon's noise problems.

The only real difference between Canon's Dual-Scale CP-ADC patent and Exmor's is that Exmor uses digital CDS and digital amplification (basically, it is an entirely digital pipeline)...I see no mention of Canon's patent referring to digital data processing on-die. There are theoretically pros and cons to both digital and analog readout, so only time will tell (assuming Canon actually IMPLEMENTS this design sometime soon) whether Canon's approach produces results that are as good as Exmor or not. Sometimes it is easier, and more accurate/precise, to apply certain kinds of processing and filtering on an analog signal rather than digital bits.

Thank you for the explanation! I got the gist of it, but I still don't understand the basics: how is it possible to read the same pixel twice simultaneously? I thought you can't eat your cake and have it too :)? I mean, wouldn't the signal become weaker if you split it?

15
I had bad experience with Adorama's customer service both times I ordered from them. In contrast, I've purchased photo gear on multiple ocasions from B & H, Amazon, BuyDig, and even Abe's without any issues.

For example, some time after ordering Canon 70-200 f4 IS, since I didn't receive shipping confirmation, I found on their web site that the order status is "canceled". Without any explanation or even notification from Adorama. I tried again with the same result. When I called their customer service, I was told, literally: "your information doesn't match... please don't order from us any more". Five minutes later I used the same credit card to purchase the lens from B & H with no problems whatsoever - after wasting a few days with Adorama for nothing.

I get it that mistakes happen and I wouldn't be upset if they made even the slightest effort to fix things or just explain what happened. Instead, all the customer "service" I received was telling me that they don't want me as a customer? Needless to say, I was glad to oblige and I haven't ordered from Adorama ever since, even if I had to pay more at another seller.

Pages: [1] 2 3 4