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Messages - Fishnose

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Apologies! You're quite right.
No, I didn't misread them - I misread you. You were indeed discussing something else than Low-Light ISO. Apologies again.

No worries.   DxOMark's ISO Sensitivity ≠ Sports (Low-Light ISO), which is exactly the point I was making about the confusion stemming from naming it ISO Sensitivity - that name seems to correspond to what you're talking about, ISO noise performance, when in fact, it doesn't.  It's confusing, and apparently you fell victim to that confusion.   :o

No, I thought you were adressing the way they measure their ISO score, the one in the Sensor Scores table where 5DMkIII gets 2293 ISO.
The other thing you were discussing is a different issue, I just missed that you were talking about something else.

You quoted the description for the SNR%18 result which is not what Neuro was talking about. He was explaining the ISO Sensitivity portion.

The text I quoted from DxO is their own description of how they test for "Sports (Low-Light ISO)". Which is the ISO value given in the sensor scores (2293 ISO in the case of the 5DMkIII).
Read their tech texts.

I have, and I suggest that you are misreading them.  I was not discussing the "Sports (Low-Light ISO)" testing, but rather what they call ISO Sensitivity, which is one of their In-Depth Measurements that you can read about here, and is completely different from the Sports (Low-Light ISO) Score you're talking about, which is one of their Use-Case Scores and is described here instead.  Please read a little more carefully, and post back if the difference is still unclear.

Apologies! You're quite right.
No, I didn't misread them - I misread you. You were indeed discussing something else than Low-Light ISO. Apologies again.

The 5DM3 image also just flat-out looked better, color-wise and tonally (several family members agreed.)
Sounds like hard science to me!  ;)

ROFL! Just what I thought.

You quoted the description for the SNR%18 result which is not what Neuro was talking about. He was explaining the ISO Sensitivity portion.

The text I quoted from DxO is their own description of how they test for "Sports (Low-Light ISO)". Which is the ISO value given in the sensor scores (2293 ISO in the case of the 5DMkIII).
Read their tech texts.

Nikon, going really fast.

"Nikon, going real fast"?

The DxO just tests the sensor.  Sony makes the D800 sensor, not Nikon.  Shouldn't all this fanboi love be giving Sony the credit?  All Nikon did was stick it in a camera "system", that by all other accounts is far inferior.

So... Way to go Sony!  Too bad Nikon f#@%ed it up by putting it in that body, but very nice job on the sensor.


I'm talking about Nikon working hard to trump their competitors by making smart moves, and Canon doing other things because they're too complacent and comfortable. If Canon decides to make their own sensors and loses market share because of it, that's known as a marketing mistake. Simple.

Case in point: Nikon D3200. Higher resolution than any Canon ever made and it's their CHEAPEST model in the new line. The image quality is apparently darn good. Yes, I now it's DX, but it's still remarkable - and a brilliant move.

If Canon wants to avoid a disastrous loss in market share they need to DO something, not sit on their behinds.

I've worked with R&D and I know exactly how this works, how companies do well and then relax. And lose.

1) ISO sesitivity - no meaningful differences except the total range (5D3 beats D800 and D4 beats 5D3)

Just to call this one out, DxOMark's ISO Sensitivity measurement isn't measuring what most people think it's measuring.  It has no direct bearing on ISO noise performance (but an indirect one, see below).  The name is perhaps misleading, maybe better to call it 'ISO Accuracy' or 'ISO Fidelity'.  What this test measures is the real ISO value (benchmarked against the actual International Organization for Standardization's criteria) vs. the ISO setting on the camera, or to put it another way, it measures how much the camera lies to you when you pick a given ISO setting. 

In the plot you can see that for ISO 50 and ISO 100, the dots for the 5DIII, D800, and D4 are all stacked on top of each other, and they're all at ISO 75 for both settings.  What that means is all three cameras are lying to you in exactly the same way - whether you set ISO 50 or ISO 100 for your shot, the exposure is actually at around ISO 75 and then pushed or pulled by the camera as needed, although the ISO value you selected is what's actually recorded in the metadata.  This lying is not new or unique - both Canon and Nikon do it routinely for fast lenses, where the incident angle of the light exceeds the refracting capability of the microlenses and exposure is 'secretly' boosted to compensate (i.e. about 1/2 stop of the light coming in at f/1.2-1.4 is not detected by a digital sensor, so the camera boosts the ISO half a stop - meaning half a stop more noise - without telling you).

Perhaps of a bit more significance is the way this plays out - if you compare just the D800 to the 5DIII and look at the ISO Sensitivity plot, you can see that the D800 is a little further off the nominal value at all the settings, with more separation at the higher ISOs.  In other words, the D800 lies to you a little more than the 5DIII (but the 5DIII is still lying).  For example, when you set both cameras to ISO 6400, the D800 is actually shooting at ISO 4211 (it's lying by 2/3-stop), whereas the 5DIII is actually shooting at ISO 5179 (it's lying by only 1/3-stop).  Translation - artificial advantage for the D800 because it's shooting at a lower actual ISO than the 5DIII for a given setting.

No Sir, this is incorrect. Your technical explanations so far have been stellar, but here you're wrong. The 'ISO accuracy' you menton is a different measurement altogether.

Quote from DxOMark concerning what their 'Sports (Low-Light ISO)' measures:

"Sports & action photography: Low-Light ISO

....Photojournalists and action photographers often struggle with low available light and high motion. Achieving usable image quality is often difficult when pushing ISO.

When shooting a moving scene such as a sports event, action photographers’ primary objective is to freeze the motion, giving priority to short exposure time. To compensate for the lack of exposure, they have to increase the ISO setting, which means the SNR will decrease. How far can they go while keeping decent quality? Our low-light ISO metric will tell them.

The SNR indicates how much noise is present in an image compared to the actual information (signal). The higher the SNR value, the better the image looks, because details aren't drowned by noise. SNR strength is given in dB, which is a logarithmic scale: an increase of 6 dB corresponds to doubling the SNR, which equates to half the noise for the same signal.

An SNR value of 30dB means excellent image quality. Thus low-light ISO is the highest ISO setting for a camera that allows it to achieve an SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits."

I love Canon, but they got caught with their pants down, marketing-wise.

Yes, success leads to complacency.
Just like the big trouble Nokia is in now. They had 37% of the whole cellphone market a couple of years ago, now they're #2 after Samsung and losing speed fast.

2 Canon guys, from R&D and Sales, are sitting out in the sun, taking a (really long) break.
Something yellow and black comes by at tremendous speed, so fast they can't really tell what it was.
"A bumblebee, maybe?" says one.
"Yeah, I guess."
And they go on relaxing.

What was it?
Nikon, going really fast.

Well, DxOMark has finally released test results for 5DMkIII.

Total: 81
Portrait (Color Depth): 24 bits
Landscape (Dynamic Range): 11.7 Evs
Sports (Low-Light ISO): 2293 ISO


EOS Bodies / Re: Um... is there a 30mpix camera on the way and when?
« on: April 15, 2012, 06:02:32 PM »
They have now seen that there are enough who are trained to believe that more MP are better and will put their money down for bragging rights.

You're basically telling me I'm an idiot because I feel I have a use for 36MP. I don't appreciate that. Choose your words more carefully.

What you really mean is YOU don't think one needs so many MP. Now that's another matter entirely. That's just YOUR little opinion.

Okay... here's KR's portrait in his own style  ;D

Ken Rockwell's images aren't overly saturated; he just sees the world more vividly than anyone else.

No, it's the other way around. He has to crank up the saturation because that's the only way he can get anything out of any subject. Without 'Vivid' his photos would all be grey & beige picnic tables and his own horrible, colorless kids.

And remember folks! Tripods are for wimps! (Says KR, and he knows)

EOS Bodies - For Video / Re: Philip Bloom's Review Canon 5d Mark iii
« on: April 01, 2012, 12:35:48 PM »
That's a very different New Zealand from the one I can see out of my apartment window!
That's because you live in Detroit now.......

The Sigma 10-20 F/3.5 is a very fine lens. Gets very good ratings at DxOMark. I have it and recommend it highly.

The Canon XF100/105/300/305 are all marketed as "professional" camcorders. For $3000 to $8000, they certainly don't seem targeted at the kiddie's birthday party market. And all of them have autofocus capability, and it's apparently fairly sophisticated. (They also have built-in lenses and fairly small sensors.) If "professionals" use manual focus, why is this capability included in these models?

Because these cameras are not meant to be used in cinematic situations. Run and gun videography often means you need to have plenty of dof all the time, and manual focus is often impossible because you've got the cam on your shoulder and there's no way you can have a focus puller running alongside. You're too busy keeping the subject in frame and keeping track of your sound guy/cables/levels/keeping down the shake etc.

Shallow dof and manual focus is a different world. A controlled world where distance to subject is often measured with a laser before each take and the focus puller sits and twiddles back and forth between markings on his remote. Try that in the real world....

Comments about tiny sensors just don't have relevance in the world of video except on a set. After all, Full HD is only 2MB, you don't need much of a sensor for that. So many other issues are more important.

Shallow dof is SO cool right now. Just because DSLRs can be used for video. Gee, wow. Who gives a toss in the real world.

Third Party Manufacturers / Re: Cancelled my D800 pre-order... !!!
« on: March 31, 2012, 10:58:28 AM »
I can't imagine what an endless string of comparisons between old camera models has to do with anything. Which camera you choose to buy and use depends on a couple of factors. How you like the camera to feel and function, and what you use it for/need it to do.
I need maximum pixel power because it often happens that a shot I take for a customer (building sites and the like) has a cool detail in it that my customer absolutely wants to use for something. So the ability to crop heavily and still have usable resolution is KING for me. I'm not a sports photographer, the fastes thing in my frame is a machine rolling by or people working and walking around.
So I'll choose a high res camera over a really fast one. Simple.
If you need speed above all else, you don't get a super-high pixel camera.
If you need a balance between the two - good speed and good resolution - you pick the middle path.
Nikon and Canon are two mighty fine makes of camera, both make exceptional bodies and amazing glass. So pick make by how you like the camera to feel and function, choose model by what you need it for... and you're done.

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