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12-30-2015, 09:33 AM   #121
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Yeah !
Thanks for the update.
6 month later than the Sonys "concurrents".


If we are lucky, 645Z complete test will be published next month.


Last edited by Zygonyx; 12-30-2015 at 09:38 AM.
12-30-2015, 12:24 PM   #122
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QuoteOriginally posted by beholder3 Quote
It smells a little fishy, yes. They indirectly publish it here:
Measurements: Excellent low noise levels - DxOMark
but keep it from the database.
I don't know. I am developing another idea what is going on ...

Look at Camera Database - DxOMark

which are their MF result. All between 2006 and 2012, and between 64 and 91 overall score. A new single entry at 2015/101 is kind of a fresh start for their MF category.

Maybe, they are finishing up a few other CMOS entries to publish a more complete picture. Would be ok, I'd say.
12-30-2015, 12:40 PM   #123
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Ok after 6 months without any comment on their part?

Sorry Falk, there may be some good reasons on their part but that delay without comment explaining why is atrocious for their corporate image and credibility.
It is a shame as I really have nothing against them. Their work isn't perfect but it is a lot better than without.
12-30-2015, 09:21 PM   #124
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QuoteOriginally posted by beholder3 Quote
.

1. "Noise" results in "ugly spots" on a photo. If you enlarge an ugly spot it gets uglier because: You perceive it more easily.

As a 36x24 (small format or "FF") sensor is smaller than a 44x33mm sensor you need to magnify the image more if you want to hang it on your wall in the same size. Thus you perceive more noise (the spots being larger) while the actual noise level per area is the exact same when using the same exposure.
I like a lot of what you say, Beholder, but this bit isn't right.

There's no magnification in the output from these cameras, as far as Dxomark is concerned.

For them, an 8"x12" print is the target, and you only need 8Mp for that, so pixels are never being enlarged, they're being down sampled from all the cameras on the market, full framed or cropped. ☺


Last edited by clackers; 12-30-2015 at 09:27 PM.
12-31-2015, 01:35 AM   #125
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If the sensor is 36x24mm, and the output is 8"x12"...
12-31-2015, 01:56 AM   #126
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QuoteOriginally posted by Kunzite Quote
If the sensor is 36x24mm, and the output is 8"x12"...
You got it.

QuoteOriginally posted by clackers Quote
For them, an 8"x12" print is the target, and you only need 8Mp for that, so pixels are never being enlarged, they're being down sampled from all the cameras on the market, full framed or cropped. ☺
As Kunzite hinted at: It's still being magnified a lot from the stamp sized sensor. They just don't magnify to the extreme level which would be represented by a "100%" on screen view, where one displayed pixel is same size for all cameras because the screen itself defines the size of the viewed pixel (even though the offer this view on their data as well under "screen").
And they magnify it all to the same, relatively small for some, print size.

As I wrote above, your and mine human viewing capabilities are limited at about 6 MPx when watching a picture from a distance equaling its diagonal (43mm FF perspective). So what they chose is not a bad idea.
12-31-2015, 03:22 AM   #127
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QuoteOriginally posted by Kunzite Quote
If the sensor is 36x24mm, and the output is 8"x12"...
It's not what I mean and you know it, Kunzite. 😁

The output is 300dpi regardless of the sensor format.

The pixels are no further apart or bigger in an APS-C image at these sizes than a FF one.

Last edited by clackers; 12-31-2015 at 04:04 AM.
12-31-2015, 04:43 AM   #128
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QuoteOriginally posted by clackers Quote

The output is 300dpi regardless of the sensor format.
Sorry, I fear I didn't get that part...

12-31-2015, 05:06 AM   #129
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To everybody discussing print magnification etc.

You make it unnecessarily complex. The point it is all about is rather simple: Noise (in general, audio, video, photo etc.) is frequency-dependent, higher frequencies being more noisy. That's a simple engineering fact.

DxO copes with that by normalizing their noise measurements to a single, predefined spatial frequency. This is how they obtain comparable figures. And it is all a photographer ever needs to know. Just trust them.

Their babble about 8"x12" print size or 8MP prints is redundant and the more technical-minded readers at DxO ignore it or use the underlying formulas directly. Moreover, it wouldn't change anything if they replaced 8MP by 2MP or 32MP and renormalized scores. Beyond that, their babble is technically correct though (except that they renormalize results rather than actually resample anything). Just may not always apply in all situations but as I daid, doesn't matter anyway.

One last remark: noise has no "size" and therefore, please avoid wording such as "magnify the noise". It is a technically meaningless sentence. For the technically inclined wanting to understand why: please google for "white noise", Wikipedia even shows a white noise image for clarification.

Last edited by falconeye; 12-31-2015 at 05:15 AM.
12-31-2015, 05:18 AM - 1 Like   #130
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QuoteOriginally posted by thibs Quote
Sorry, I fear I didn't get that part...
300dpi is what DXOMark in their infinite wisdom have adopted as the printer resolution for this imaginary 8Mp picture all these worshipped stats are based on.

A monitor might be 100dpi by comparison.
12-31-2015, 05:48 AM   #131
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QuoteOriginally posted by clackers Quote
A monitor might be 100dpi by comparison.
the old CRT used to be 72 dpi. now retina screen are betwwen 230 and 330 dpi. What you get on high end screen is close to what you can get with your print*.

*There is of course some difference in color and grey variation, if screen is not properly calibrated.
12-31-2015, 05:51 AM   #132
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Interesting...
12-31-2015, 06:05 AM   #133
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QuoteOriginally posted by falconeye Quote
To everybody discussing print magnification etc.

You make it unnecessarily complex. The point it is all about is rather simple: Noise (in general, audio, video, photo etc.) is frequency-dependent, higher frequencies being more noisy. That's a simple engineering fact.

[...]

One last remark: noise has no "size" and therefore, please avoid wording such as "magnify the noise". It is a technically meaningless sentence. For the technically inclined wanting to understand why: please google for "white noise", Wikipedia even shows a white noise image for clarification.
Simpler, actually. It helps you visualize, which is difficult if you stick with the engineering approach

The statement was about magnifying the image (which you will effectively do, when printing), and it was not about the DXOMark's normalization system.

---------- Post added 31-12-15 at 03:16 PM ----------

QuoteOriginally posted by clackers Quote
It's not what I mean and you know it, Kunzite. ��

The output is 300dpi regardless of the sensor format.

The pixels are no further apart or bigger in an APS-C image at these sizes than a FF one.
I know it's not what you mean, the question is: what do you mean?

I'm not sure why you're talking about pixel spacing here... or even if you really are talking about pixels (dimensionless, they're only information) and not sensels (sensor elements, which are physical entities)
Magnification is a simple matter of relating the original image (that is, the part of the image projected by the lens which we're actually using) to the final image (as printed or otherwise displayed on a physical media). While the digital image at some point will temporarily lose its dimensional characteristics, this abstraction IMO is still very useful.

Last edited by Kunzite; 12-31-2015 at 06:16 AM.
12-31-2015, 06:16 AM   #134
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QuoteOriginally posted by falconeye Quote
You make it unnecessarily complex.
Sorry, but inability to explain things to those who don't care for textbook wording is making things worse and worse.

The whole issues with everybody getting parts wrong are not about the content (which is high school level physics at worst), it is about the ability to explain things in a way the readers can follow easily and visualize easily.

QuoteOriginally posted by falconeye Quote
frequency-dependent ... predefined spatial frequency.... renormalized...white noise
All irrelevant for any photographer trying to understand the causal relationships of where to expect more or less noise in his pictures. While probably well meant, not quite helpful outside a high school physics classroom.

And noise is "small unwanted spots of wrong brightness/color" in a picture in that regard. Nothing more.

Side note:
If somebody has a very good eyesight >100%, let's say 150%, all pictures will "be" a lot more noisy to him (!) as well.
Because their eyes do less "downsampling" of all these ugly spots.
12-31-2015, 08:17 AM   #135
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QuoteOriginally posted by clackers Quote
300dpi is what DXOMark in their infinite wisdom have adopted as the printer resolution for this imaginary 8Mp picture all these worshipped stats are based on.

A monitor might be 100dpi by comparison.
300dpi is a standard for print. It approximate the max resolution your eyes can distinguish so basically the idea is you don't need more than that. You may find articles that peoples tend to prefer even higher resolution prints on blind test even if the can't always say why or articles that say 100dpi is enough. But as a recognized standard for high quality, 300dpi is good start.

A4 (approximately 8'x12") is also a printing standard, used by most printers (at least were I live), it also rougly match the size of a typical magazine or book sheet. Sure there are other formats depending on your country etc but this is often similar size.

8MP ensure that you actually get 300dpi on an A4 print so very high quality and is also practical because most camera can achieve that resolution. It make more sense than say 1MP or 200MP.

We could say it should be 6MP or 12MP, that the format should be another one or that 200dpi would be a better choice... But this is of no importance. It doesn't mesure sharpness but the dynamic range, signal to noise ratio and color deph of camera in a way that is actually comparable.

If you want DxO also provide the results at full resolution.

Ironically the new standards for cinema and modern TV are also approximately 8MP. To me their choice while not perfect make lot of sense. Critiizing them is easy, it may not be relevant and you or me may not be able to do better.
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