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09-28-2010, 04:19 AM   #16
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The contrast AF in live view is very quick indeed (not that I use it), nearly as good as the NEX-3 and that's saying something.

09-28-2010, 06:37 AM   #17
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Just received a message from GordonB(on another site) with the following:

QuoteQuote:
John, no need to post a correction, as I have further results that indicate that the Dynamic Range (DR) of the K-5 at ISO 80 is even better than the information that I had previously, and from my posting where Falk Lumo (falconeye) got his results.

I received an ISO 80 DNG raw image from one of the Beta version cameras at Photokina. This contains a strip of 10 black masked-to-light columns at the left edge of the image in landscape orientation which for this particular sample was offset by about 69 14-bit levels, meaning that the black read noise was not clipped to zero at all and the standard deviation was therefore not affected by such clipping. The standard deviation of these black level columns averaged about 1.1 14-bit levels, meaning that the DR *for this particular sample in these particular conditions* had a value of 16383 (14 bit maximum) : 1.1 or about 13.86 stops at ISO 80 for 16.2 MP on an APS-C sensor in DxOMark terms. This means that the "standard rated 8 MP equivlalent" DxOMark DR score would be about 14.36 stops, and makes the K-5 potentially the current low ISO DR king of all cameras measured so far. If these results are solely a function of the sensor, it is very likely that Sony and Nikon models using a similar sensor will have scores something about the same.

This means that these cameras can indeed use a 14-bit raw output file effectively, although it must be noted that these extra bits will only be of any use for ISO's below about ISO 640 and then only for the very deepest shadow details darker than about 10.7 stops below the bright clipping level. For brighter tones and/or for higher ISO's, the extra bits do nothing but make the resulting raw file sizes larger.

Regards, GordonBGood
So there you have it. Looks like the K-5 will be the new DR king of the hill!
09-28-2010, 06:43 AM   #18
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QuoteOriginally posted by JohnBee Quote
So there you have it. Looks like the K-5 will be the new DR king of the hill!
Why do you think that other cameras with the same Sony sensor will be worse?
09-28-2010, 07:03 AM   #19
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QuoteOriginally posted by Edvinas Quote
Why do you think that other cameras with the same Sony sensor will be worse?
Come on! everybody knows the answer to that!
Because they are not a Pentax.

09-28-2010, 07:11 AM   #20
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as i understand things these aren't the same chips as in different cameras - they are made by sony but with some modifications as per pentax's instructions - hence why cameras like the d7000 can have lesser base iso range while still using a 16mp sony chip

but seeing that the k5 has the best dynamic range of any camera so far is amazing

think that will tip the balance and tempt people into buying that weren't already considering it (should it be proven correct anyway)
09-28-2010, 07:20 AM   #21
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QuoteOriginally posted by stormcloud Quote
as i understand things these aren't the same chips as in different cameras - they are made by sony but with some modifications as per pentax's instructions - hence why cameras like the d7000 can have lesser base iso range while still using a 16mp sony chip

but seeing that the k5 has the best dynamic range of any camera so far is amazing

think that will tip the balance and tempt people into buying that weren't already considering it (should it be proven correct anyway)
I agree wholeheartedly!

K-5, ISO6400 (left) - D700 ISO6400 (middle) - A55 (right)


K-5 and A55, apparently have the same sensor, but ...
09-28-2010, 07:32 AM   #22
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QuoteOriginally posted by Rondec Quote
Yes, thank you Falk for a very thorough summary of the K5. Having someone like yourself on the ground there really is beter than me being there myself, since there is no way that I would have been able to touch on all the things that you analyzed there.

I definitely think that the sensor is exciting. I love shooting with the K7 already -- it just feels better to shoot with than my K20 and if the few quibbles are fixed on it, it could be "the last camera" I "need" for quite awhile (and I bought a K100, K10, K20 and K7).
LOL, sorry for OP, but from your history the K5 will be the last camera you'll need until the next one appears
09-28-2010, 08:25 AM   #23
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Johnbee, thanks for posting - do you not have crops showing detail?

09-28-2010, 08:31 AM   #24
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QuoteOriginally posted by Big G Quote
Johnbee, thanks for posting - do you not have crops showing detail?
I do have detail, but... since they are different scenes(unfortunately), I saw no sense in posting that(not much to relate too unfortunately).

I guess at best, this is nothing more than looking at noise patterns between camera's at similar ISO's. Which isn't all that bad when you think about it since noise can be measured this way also. The only downside as mentioned, is that we don't get to see detail retention at this point. Well... not in a comparative way that is.
For what it's worth, the K-5 RAW sample does have plenty of detail from which to evaluate.
09-28-2010, 09:23 AM   #25
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QuoteOriginally posted by stormcloud Quote
but seeing that the k5 has the best dynamic range of any camera so far is amazing
Let's be serious: noone has done proper testing yet.
And GordonBGood did not analyze D7000, Sony RAW files yet, did he? Also he states in DPReview forum, that other cameras with this 16 megapixel Exmor sensor should perform on the level of K-5.
09-28-2010, 09:31 AM   #26
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QuoteOriginally posted by Edvinas Quote
And GordonBGood did not analyze D7000, Sony RAW files yet, did he?
No word of that as of yet.
However the RAW's are available so there's hope.

QuoteQuote:
Also he states in DPReview forum, that other cameras with this 16 megapixel Exmor sensor should perform on the level of K-5.
Nothing wrong with that
09-28-2010, 10:21 AM   #27
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QuoteOriginally posted by Edvinas Quote
Let's be serious: noone has done proper testing yet.
And GordonBGood did not analyze D7000, Sony RAW files yet, did he? Also he states in DPReview forum, that other cameras with this 16 megapixel Exmor sensor should perform on the level of K-5.
not all depends from sensor !!! There is AA filter and other stuff which plays in picture quality. We even don't know how different can be these Sony 16 megapixel sensors.
09-28-2010, 10:22 AM   #28
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QuoteOriginally posted by JohnBee Quote
For what it's worth, the K-5 RAW sample does have plenty of detail from which to evaluate.
That's from "my" RAW, the one with the chart and red tree, correct?

QuoteOriginally posted by JohnBee Quote
No word of that as of yet.
However the RAW's are available so there's hope.
Gordon relies on his own RAW reader which is a great thing. It supports PEF (and DNG obviously). I am not so sure about other formats though.

Gordon's "trade mark" is to look at pixels which are obstructed and receive no light, still are in the raw file. He takes their values and compares to the illuminated ones, even if almost dark. From that exercise, he learns a lot. Like ful lwell capacity. It's an ingenious idea!
QuoteOriginally posted by Vaikis_ Quote
other stuff which plays in picture quality. We even don't know how different can be these Sony 16 megapixel sensors.
The Sony SLT A55 receives a bit less light because of the semitransparent mirror. ISO should be shifted before being compared.
09-28-2010, 10:30 AM   #29
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QuoteOriginally posted by falconeye Quote
That's from "my" RAW, the one with the chart and red tree, correct?
Yes correct. I took the liberty of running some superficial evaluations(patch samples) between that RAW and the D700 RAW of equal ISO. I saw the full size JPG's as well, but they seemed to have NR applied to them:



So I processed neutral RAW as a result.





K-5, ISO6400 RAW*


D700, ISO6400 RAW*


K-5, ISO6400 RAW*


D700, ISO6400 RAW*


And finally... a crop of each sample along with the A-55.



TBH. the K-5 image cleans up beautifully. And I'm dying to see how it would compare to a base file of the same scene. But at this stage, there are not doubts that it can keep up with the D700 FF.
09-28-2010, 10:39 AM   #30
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Oh, the camera is beginning to shape up.
DR seems to be very promising, DFS seems to be controllable, memory buffer is still uncertain, and how about shutter blur?

I'm very close to hitting the pre-order button (price is acceptable in Sweden, especially for the rest of this month (a short time offer)). But I told myself to wait for dxomark and other test/reviews, to have patience, be cool, wait for the bugs to be ironed out. Sometimes though I just don't listen to myself...
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