August 23, 2014, 05:38:38 AM

Author Topic: IQ comparison; or how meaningful is DXO  (Read 9319 times)

Mt Spokane Photography

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Re: IQ comparison; or how meaningful is DXO
« Reply #15 on: September 03, 2013, 12:07:48 PM »
DXO measures the sensor characteristics.  Those are hard facts.  DXO does not test cameras.
 
For those that understand this, the information can be useful in selecting a camera that has a sensor which meets your special needs.
 
Unless its a extreme application, the photographer is 90%, the lens is 9.99 % and the body makes little difference to IQ.
 
Since DXO does not test bodies for other things that may matter to photographers like metering accuracy, their attempting to put a number to a camera body based on sensor testing is of little value to me, but the raw data is valuable.
 
However, if you are one who needs a particular sensor characteristic, understanding the strengths and weaknesses of your sensor might be important.  So far, I have found lenses to be so much more critical, that the sensor makes little or no difference, unless its defective.

Joynt Inspirations

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Re: IQ comparison; or how meaningful is DXO
« Reply #16 on: September 03, 2013, 12:10:57 PM »
I'm game.

1. DCBA
2. ADCB
3. DBAC
4. BDCA
5. ACBD
6. DBAC

Fool me once …

hutjeflut

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Re: IQ comparison; or how meaningful is DXO
« Reply #17 on: September 03, 2013, 01:18:30 PM »
its just not possible to siply rank them as each row has different pixtures that have different qualitys better like colour sharpness and noise are not always equally good on each shot.

1.  D simply beats all the others both in detail and sharpness but on it seems somewhat lower on the exposure side as its a little darker resulting in lower saturation.

2. D and A seem the have about the same iso preformance but A seems to be slightly out of focus and a little flat colour wise while C seems to be best colour wise but had poor details and noise preformance.

3. D is the best on everything here

4. B seems to have the best noise preformance but seeing all the details of the blocks has fallen away this immage on full size will look flat and lack detail so your mostlikely better off with D which had the second best noise preformance but maintains detail.

5. D has the best noise preformance but lacks detail and saturation and contrast making me think C would give the best end result  as its luminous noise mostly and has plenty detail and saturation. A has more detail but far worse noise preformance making you lose detail on noise reduction.

6. B has the best colour reproduction and a nice even move from dark to light blue while A as the most detail/sharpness/contrast and D has the best noise preformance.

so depending on what you look for different photos might fit your need best.

aj1575

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Re: IQ comparison; or how meaningful is DXO
« Reply #18 on: September 04, 2013, 02:31:19 AM »
its just not possible to siply rank them as each row has different pixtures that have different qualitys better like colour sharpness and noise are not always equally good on each shot.

....

so depending on what you look for different photos might fit your need best.

Thanks, a very nice analysis.

aj1575

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Re: IQ comparison; or how meaningful is DXO
« Reply #19 on: September 04, 2013, 02:52:36 PM »
Here is the comparison with the camera models and the settings of the pictures taken.

I leave it to you to judge your results; I will make some kind of statistics later.

« Last Edit: September 04, 2013, 02:54:12 PM by aj1575 »

ajfotofilmagem

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Re: IQ comparison; or how meaningful is DXO
« Reply #20 on: September 04, 2013, 03:03:11 PM »
Here is the comparison with the camera models and the settings of the pictures taken.

I leave it to you to judge your results; I will make some kind of statistics later.
Well, I guessed right the line 3-D image was even canon 70D. :D Overall, my preferences this blind test, was also Canon 6D and 70D. By coincidence, are these cameras I would buy right now. ;)
« Last Edit: September 04, 2013, 03:52:31 PM by ajfotofilmagem »

ajfotofilmagem

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Re: IQ comparison; or how meaningful is DXO
« Reply #21 on: September 04, 2013, 04:03:49 PM »
It did not seem very fair to compare images of APS-C vs full frame. But in the end, the results were what one might expect. No big surprise. Just a little disappointed with the sharpness of the D7100, which having no AA filter, I expected to be sharper than other APS-C. ::)

privatebydesign

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Re: IQ comparison; or how meaningful is DXO
« Reply #22 on: September 04, 2013, 08:42:59 PM »
I came out with this, I didn't cheat for what that is worth.

D,C,B,A
A,D,C,B
B,C,D,A
B,C,D,A
C,D,A,B
D,A,B,C

So the 70D didn't fair too well for me, but the 6D did. However small crops of jpegs that haven't been normalised really don't illustrate much.
The best time to plant a tree is twenty-five years ago. The second best time is today.

Pi

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Re: IQ comparison; or how meaningful is DXO
« Reply #23 on: September 04, 2013, 10:12:47 PM »
What does this have to do with DXO?

ajfotofilmagem

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Re: IQ comparison; or how meaningful is DXO
« Reply #24 on: September 04, 2013, 10:28:11 PM »
What does this have to do with DXO?
In this blind test, each person chose the images that seemed best. Now we know what we were looking cameras, can compare with the DXO ranking. In my case, the images that I found most enjoyable were 70D and 6D. Two models with DXO scores worse than the competitors. For me, no surprise. The criteria DXO does not show which camera is the ideal image to my eyes.

privatebydesign

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Re: IQ comparison; or how meaningful is DXO
« Reply #25 on: September 04, 2013, 10:38:15 PM »
It depends on what you think the images illustrate.

I don't consider them relevant to my buying decisions for two key reasons:
  • They are not normalised, that is, they are different sizes at 100%, this is not how I use images, I want a comparison of a set reproduction size, if I am making a 12" x 18" print I don't care how many pixels I have, I just need that size.
  • I don't have any use for jpegs, indeed I practically don't use them at all, I even send 16 bit data to my printers now. Jpeg output is irrelevant to me, I need to know what I can get out of the RAW file and how much time it takes to get it.
The best time to plant a tree is twenty-five years ago. The second best time is today.

Pi

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Re: IQ comparison; or how meaningful is DXO
« Reply #26 on: September 04, 2013, 10:42:10 PM »
What does this have to do with DXO?
In this blind test, each person chose the images that seemed best. Now we know what we were looking cameras, can compare with the DXO ranking. In my case, the images that I found most enjoyable were 70D and 6D. Two models with DXO scores worse than the competitors. For me, no surprise. The criteria DXO does not show which camera is the ideal image to my eyes.

Some of the crops are OOF, you have different NR applied to them, etc. Your title is too provocative for what you are doing. You do not need to take cheap shots at DXO.

CR00

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Re: IQ comparison; or how meaningful is DXO
« Reply #27 on: September 05, 2013, 02:55:38 PM »
I think he mentioned at the beginning of the post that he took the pictures from dpReview, and arranged them in 6 rows with 4 pictures each.  I think you can try it at http://www.dpreview.com/reviews/nikon-d7100/20 and see it for yourself.

dtaylor

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Re: IQ comparison; or how meaningful is DXO
« Reply #28 on: September 05, 2013, 04:12:39 PM »
DXO measures the sensor characteristics.  Those are hard facts. 

No, they are the results of DxO's testing process and interpretations. There's quite a bit of disagreement as to whether or not DxO's tests are accurate and/or meaningful.

qwerty

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Re: IQ comparison; or how meaningful is DXO
« Reply #29 on: September 05, 2013, 05:25:38 PM »
DXO measures the sensor characteristics.  Those are hard facts. 

No, they are the results of DxO's testing process and interpretations. There's quite a bit of disagreement as to whether or not DxO's tests are accurate and/or meaningful.

I do not think there is much disagreement that their sensor tests, methods, and results are accurate and meaningful (at least for some uses).  The disagreements are to 1) whether the reported scores (scores, as opposed to test results) are fair, useful, meaningful or what-have-you 2) whether the differences matter for a given user and 3) the fact the DxO only measures sensor performance, not camera performance (and does not claim to do anything different).
« Last Edit: September 05, 2013, 05:29:54 PM by qwerty »