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12-11-2012, 08:04 AM   #46
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QuoteOriginally posted by Enkhbayar Quote

btw, dxomark missing one big performance measurement, focus performances including accuracy, speed, sensitivity!
DXO Mark has nothing to do with accurancy, speed and sensitivity of AF. And it depends on lens and EV.
They test the SENSORS.

12-11-2012, 08:19 AM   #47
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QuoteOriginally posted by ogl Quote
It looks like this
I sense many questions from these sample. ie. were they shot in RAW, identical scenes, lens, lighting etc?

QuoteQuote:
K-5's result is in the middle. Good resolution and no good acutance
K200D is the last. I would say it's K-5IIs.... Good resolution and good acutance

I prefer the last one

If we apply to the second picture more sharpness we will get ALIASING and HALOES.
Without telling people what to do, I think you would be better off using a deconvoluted sharpening method such as Smart Sharpen or Raw Therapee contrast sharpening in cases where the AA filter becomes the target of obstruction. That being said, I think I did some tests with the K200D vs the K-5 some time ago for another thread, at which point, the results dwindled down to sharpening method. At which point I believe the OP announced he was only interested in JPG shooting. Though in the end, I seem to recall where the K-5 JPG's could also be sharpened to exhibit the same level of accutance as the K200D.

At any rate, I'll have a quick look around to see if I can't find those samples. Though I think this really comes down to sharpening. Especially if/when we consider where the K-5 holds a resolution advantage over the K200D.

Last edited by JohnBee; 12-11-2012 at 08:40 AM.
12-11-2012, 08:39 AM   #48
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QuoteOriginally posted by gazonk Quote
Actually I think Olympus did just the right thing for the Exmor sensor. I wish Pentax had did the same, then I could use my K-5 without using -0.3 - -0.7 EV all the time.
I'm pretty sure that's a separate issue.
12-11-2012, 09:10 PM   #49
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DxOMark - Comparisons
This is the page that interested me. I hope Pentax can get there ISO performance up.

12-11-2012, 10:00 PM   #50
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QuoteOriginally posted by Fl_Gulfer Quote
I hope Pentax can get there ISO performance up.
That would indeed be nice. But to really boost the low-light ISO into the realm of the D800 or D600, as DxO note, a larger FF sensor would be needed to catch more light, whilst preserving the same pixel quality of the K-5. So unless Sony makes a break through in it's APS-C sensor tech, or Pentax does a FF, low-light ISO at K-5 levels may be as good as we can expect for a while from Pentax.

Having said that, the FF 5D3 according to DxO only has a 1 stop advantage over the K-5 at low-light, and the D800/D600 may also 'only' be 1.5 - 2 stops ahead of the K-5. That's certainly noticeable but not light years ahead of K-5/D7000 grade cameras.

Particularly since the K-5 does have a good ability to hold onto detail at high ISO, and achieve high sensitivies without (for example) the sort of disturbing banding that even some FF sensors suffer from when doing low light.
12-11-2012, 10:09 PM   #51
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QuoteOriginally posted by Fl_Gulfer Quote
DxOMark - Comparisons
This is the page that interested me. I hope Pentax can get there ISO performance up.
as i said before in this thread,
almost nothing is improved on sensor recent years. it is only upgrading the algorithm, firmware, and AF system.
now the sensor High ISO performance is roughly matter of sensor size.

today nikon's best aps-c sensor score is around 1200. according to FF sensor size is 1.5*1.5 times than the aps-c, the high ISO score would be 1200*2.25=2700. today nikon's best FF sensor score released in this year is around this figure....
12-11-2012, 11:33 PM   #52
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The relation between two SNRs 18% for a sensor 1 with a surface area of and sensor 2 with an area of is :


how to compare SNR
http://www.dxomark.com/index.php/Publications/DxOMark-Insights/Canon-500D-T1...noise-analysis

The pixel size of 5D Mk III - 6.08, Nikon D600 - 5.9, K-5II - 4.75.

Last edited by ogl; 12-12-2012 at 05:44 AM.
12-12-2012, 01:58 AM   #53
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QuoteOriginally posted by ogl Quote
The pixel size of 5D Mk III - 6.08, 600D - 4.84, K-5II - 4.75.
?? Which 600 model?

Nikon D600 is 5.9, Canon 600D is only 4.17.

12-12-2012, 06:39 AM   #54
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Made some mistakes with calculation of Theoretical Delta (dB) - I will remake and put real data of SNR comparision of K-5IIs and 5D Mk III and D600.
12-12-2012, 07:11 AM   #55
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QuoteOriginally posted by ogl Quote
It looks like this
Hmm. I tried to compare some K-5 and K10 shots in my library, restricting myself to low ISO shots with the DA35 at f/4-f/5.6, and couldn't really see such big difference (except that more of the K10d shots were slightly off in focus ).
12-12-2012, 08:06 AM   #56
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K-5 and K200D, K10D and K-7

As a difference of 3 dB represents a difference of 1 stop
Attached Images
 

Last edited by ogl; 12-12-2012 at 08:57 AM.
12-12-2012, 09:05 AM   #57
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K-5 and K-30. Red - K-5 is better, yellow - K-30. I can say no any difference. At 3200 and 6400 - K-30 is 1/3 stop better.
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12-12-2012, 06:58 PM   #58
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QuoteOriginally posted by ogl Quote
K-5 and K200D, K10D and K-7

As a difference of 3 dB represents a difference of 1 stop
wow wow here's all specialists.
I would like to see some autofocus performance tests ...
12-12-2012, 07:27 PM   #59
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QuoteOriginally posted by Enkhbayar Quote
I would like to see some autofocus performance tests ...
Learn more about DxO. They do sensor and lens tests, not AF tests.

There are AF performance tests out there - look here (PDF - 5MB) for example. Pentax does very well. There are also lots of discussions on these forums about AF.
12-12-2012, 09:29 PM   #60
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QuoteOriginally posted by rawr Quote
Learn more about DxO. They do sensor and lens tests, not AF tests.

There are AF performance tests out there - look here (PDF - 5MB) for example. Pentax does very well. There are also lots of discussions on these forums about AF.
thanks for the pdf.
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