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08-30-2015, 07:00 PM   #76
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why is the sports/ISO on DXOmark on the K3II lower than the K3 ,as the same sensor??

08-30-2015, 09:12 PM   #77
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QuoteOriginally posted by Shanti Quote
why is the sports/ISO on DXOmark on the K3II lower than the K3 ,as the same sensor??
It's not a huge difference, especially when you look at the curves.
Plus different firmware etc.
08-30-2015, 11:13 PM   #78
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QuoteOriginally posted by rawr Quote
It's not a huge difference, especially when you look at the curves.
Plus different firmware etc.
And let's not forget the precision of measurement. In the end, both camera have the same score and I think it is not really possible to see any difference between the 2.
08-31-2015, 03:34 PM   #79
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QuoteOriginally posted by Shanti Quote
why is the sports/ISO on DXOmark on the K3II lower than the K3 ,as the same sensor??
An interesting observation.

The difference is within measurement errors (and the overall score the same). Nevertheless, analyzing the measurements at DxO carefully is a good way to learn about said measurement errors.

The reported SNR values of K3 and K3-II are the same. However, DxO measures a slightly lower true ISO value for the K3-II, compared to the K3. This then translates over to a slightly worse Sports score.

However, I don't think the calibrated ISO sensitivities reported by DxO reflect the truth. It rather shows the limitation of DxO measured ISO calibration. It is a tricky measurement to start with, based on a tedious evaluation of clipping luminosity per color channel. Either this, or sample variation in quantum efficiency is this high.

E.g., at ISO400, calibrated ISO is reported as 359 vs. 380. A difference of 5%. I suggest this is the precision DxO is capable of achieving. The sports score can deviate by as much too. However, in practive the difference in the sports score will be smaller because it is affected by a dynamic range threshold which is less dependend on iso calibration.

Nevertheless, I take home the insight that ISO calibration is DxO weak spot wrt accuracy and accuracies better than 5% shouldn't be expected.


Last edited by falconeye; 09-08-2015 at 01:37 AM.
08-31-2015, 05:25 PM   #80
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QuoteOriginally posted by Teddy Quote
A7RII's DxO score already come out,
it's 98 !
With Sony's lossy RAW compression, Pentax should again have no problem getting more out of whatever Sony sensor is the FF camera than Sony engineers can get out of it in their cameras.
09-01-2015, 12:03 AM   #81
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QuoteOriginally posted by cheekygeek Quote
With Sony's lossy RAW compression, Pentax should again have no problem getting more out of whatever Sony sensor is the FF camera than Sony engineers can get out of it in their cameras.

Funny you say that... Many can't see any visible difference between different levels of JPEG compression when working on different high quality settings. I don't see why it would be different from a Raw perspective.
09-01-2015, 12:37 AM   #82
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To be true, the difference would lie in the impact of compression on DR.
I don't think this is significantly the case : look at K-3 compared to A6000...
09-01-2015, 03:16 AM   #83
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DxO are about measurability. They can measure objectively differences that are difficult to see even when comparing side by side. I think Pentax might achieve slightly more DR all over the ISO range, putting it a few points in front of Sony cameras with similar sensors. Especially if they are allowed to enable uncalibrated ISO 80, i think they could pull out some extra DR points from the sensor. The DR score are purely measured at the lowest ISO, no matter what that ISO might be.

Thats one of the reasons K-3 scores lower then K-5 in the DR category. (ISO 100 vs ISO 80)

09-01-2015, 04:21 AM   #84
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QuoteOriginally posted by cheekygeek Quote
With Sony's lossy RAW compression ...
Sony RAW file format does not negatively impact DxO measurements.

Said measurements are achieved on sample patches which Sony's RAW format compresson is not lossy for (except for some tone mapping effects).

I wonder why so many people post so much stuff with so little knowledge ...

Sony's RAW format is lossy around high contrast edges only, visible only if both sides of such edges are corrected in tonality to become both visible. There are famous examples like star trails in front of a nebula after the typical heavy astro post processing. But nothing which would influence DxO scores.

Last edited by falconeye; 09-08-2015 at 01:37 AM.
09-08-2015, 12:45 AM   #85
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Fall is coming and still no 645Z on DxO yet. It's quite long after the testing to be online.
09-08-2015, 01:11 AM - 3 Likes   #86
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Tests have been achieved with 645Z and 4 lenses provided by Ricoh Imaging Europe end of last august.
Tests are taking place NOW with 645D and a brunch of lenses RI didn't provide DxO with. Amongst these tests, are intercalibration controls with 3 lenses.
They are planned to finish end of september 2015 (future new dedicated thread to come).
Then, sometime will be needed for cross-controls & chekings, and thereafter lauch of the body's and optical modules plug-in.
My understanding is that DxO Lab intends to put into production the whole 645 system. That is supposed to be effective sometime as from next october.
But of course the DxO Mark sensor results for the two bodies could be made public before end of october.

Last edited by Zygonyx; 09-08-2015 at 01:29 AM.
09-14-2015, 05:41 AM   #87
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K3 II still lagging behind DxO own camera by 5 points Tests and reviews for the camera DxO ONE SuperRAW Plus - DxOMark
Isn't that test a bit unfair? Test your own camera at best possible setting but not the competition? If they're posting that they should also test pixel shift in K3 and Olympus and stack 4 RAWs from any other camera to see what the effect would be. I've seen a video where guy shot about 200 frames (stitching and overlaying them on top of each other) with K200D and after combining them got the same quality as from Nikon D800.
09-14-2015, 07:38 AM   #88
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Yes it is.
They intentionnaly test their new product with an unfair protocol, or should do the same with other file-optimisation processes available on the market.
Even if the frame-rate is different.
That's bad for their credibility.
09-14-2015, 02:57 PM - 1 Like   #89
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QuoteOriginally posted by gfurm Quote
Isn't that test a bit unfair?
Yes, they sold part of their credibility to promote their hardware product.

But to give them credit, they list their camera w/o the feature too, and actually at the same score as other cameras featuring the same Sony 1" 20MP Sony sensor.

BTW, the Sony (e.g., RX100mkIII) comes with an app which stacks images in camera, into a single RAW with incredible dynamic range. That's a fantastic feature you find as the app to capture smoothed flowing water. In just 30s, you end up with an ISO 1 RAW image from 80 frames Stacking in post processing is tedious and time consuming, this Sony app is great and every camera should have this feature.

Pentax can do the same with the multiexposure option available in the menu.

Therefore, Sony and Pentax should both qualify as "SuperRAW Plus" cameras too ...

And that has nothing to do with the pixel shift feature ...
09-14-2015, 04:19 PM   #90
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QuoteOriginally posted by falconeye Quote
Pentax can do the same with the multiexposure option available in the menu.
One day, we may also be able to combine (in-camera) focus stacking AND multi-exposure image stacking. While that would require a lot of images and CPU power, it seems increasingly do-able.
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