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11-05-2010, 01:29 AM   #61
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QuoteOriginally posted by falconeye Quote
However, real sports photography would actually go into the "unsafe" area and accept a certain level of grain to make fast pace action shots feasible.
Absolutely. While I find the number very informative, I don't agree with calling it "sports".

("Threshold of compromise" is a better term but would still need explaining so it makes little difference!)

11-05-2010, 09:15 PM   #62
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I have found the report spot on for me. I only shoot birds and that is a sport. I used to think it was hogwash. But now i think it is spot on. I have the k-x and k-7. both reports are exactly where i shoot. K-x not above 800 k-7 not above 500. I think it is amazing how acurate they are.
11-05-2010, 10:22 PM   #63
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so, with this DxOMark evaluation out, are we now going to diss-off the K-r?

I think remember at some point that most people were very impressed with the k-r improvement over the k-x. is that all gone because this and this says it's not what it was suppose to be as it was prior to DxOmark?

I think the interested party should really think what he/she is looking for and suppose to get in a camera versus what he/she thinks what a DxOmark suppose to give to him/her. what does the DxOmarK stats stands for? is it instrumental for the person's work or it's just numbers that is made to believe that something is better and that he/she would become a better photographer? what amount of differences or gap in IQ performance is deemed substantial which is worth the consideration? I have no problem with these DxOmark evaluations but the problem with it is the misconception that it brings to some unknowing people who mostly would based something good or better on the DxOmark scores. even the ISO difference, especially bar graphs create misconceptions.
11-06-2010, 02:10 AM   #64
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QuoteOriginally posted by Pentaxor Quote
so, with this DxOMark evaluation out, are we now going to diss-off the K-r?
no
it just shows that the Kr is what we thought it would be... a Kx with upgrades and that really isn't bad since the Kx is a great entry cam

11-06-2010, 02:23 AM   #65
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QuoteOriginally posted by dankoBanana Quote
no
it just shows that the Kr is what we thought it would be... a Kx with upgrades and that really isn't bad since the Kx is a great entry cam
so it's most likely a k-x replacement. that makes sense especially for it's price. the K-5 however, IMO is in really a different bracket.
11-07-2010, 12:13 AM   #66
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k7 was a disappointment over k-x :] so is it nice to expect pentax to behave in same way ? so they should produce more capable cameras without weather sealing and sell it for almost free ?
k-r is just as i expected, may be af should ve been faster iso performance is decent and build quality feels better than k-x. handling camera is much more better than k-x too, it just fits in my hands.
11-09-2010, 09:17 AM   #67
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QuoteOriginally posted by WerTicus Quote
Why would anyone expect the K-r to perform significantly better than the K-x it is the same sensor. The measurements showing its slightly worse could well be caused by a different capacitor they used somewhere....
Not according to Ned Bunnell:

QuoteQuote:
The sensor in the K-r is new. Yes, it’s 12MP like K-x’s, but it is a new design and photographers will see an improvement in IQ because of this.
Speaking to Pentax at PhotoPlus Expo in New York | Enticing the Light

I don't think such a statement would be made in that way if it wasn't different. I get after Ned as much as anyone but I have never found him to be a liar.
11-09-2010, 09:33 AM   #68
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QuoteOriginally posted by Blue Quote
I get after Ned as much as anyone but I have never found him to be a liar.
He's no liar AFAIK. Very respectable person.

But he can only tell what he is being told himself. There must have been a reason why to change the sensor (and it isn't the same -- the differences are marginal but not zero). And the exact details must have been lost in translation. Maybe it was planned to be an upgrade which turned out not to be. Then, ask Sony why this has happened, not Ned.

11-09-2010, 11:50 AM   #69
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QuoteOriginally posted by einstrigger Quote
I don't think I'm understanding the Sports Low-light ISO score.

K-r: 755
K-x: 811
D3100: 919

I don't base my purchases on DxOMark, I'm just trying to understand how they're relaying their info. Is a higher value supposed to be better? Or is the SNR 18% chart that they have a better measurement?
very good point. if, as stated by somebody bellow (couldn't be bothered to check, sorry) that represents the maximum "acceptable" iso, here is the math:

k-r vs k-x: roughly 0.1 stop difference (yeah, zero point one. aka irrelevant)
k-r vs d3100: 0.28 stop (so less than a third of a stop, already "significant", but only just. not a deal breaker imho)
k-x vs d3100: 0.18 stop

for whomever is curious: one stop in iso is exp of 2 (so double the iso, go up one stop, halve, go down one stop). so the above was calculated as log_2(iso1/iso2)=stops (maybe somebody can call me on it if i'm doing something silly).

i personally think dxomark is pretty cool, and useful, if used with reason of course.
11-09-2010, 01:03 PM   #70
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QuoteOriginally posted by einstrigger Quote
I don't think I'm understanding the Sports Low-light ISO score. [...]
Is a higher value supposed to be better? Or is the SNR 18% chart that they have a better measurement?
A simple answer first:

The "Sports Score" is the ISO number where the decreasing 18% Gray SNR (print) curve crosses the 30 dB SNR threshold.

So, higher is better.

Some people set their Auto-ISO range to 100 ... SportsScore and it seems to be a valid choice. Results of 700 ... 900 would be indistiguishable to the naked eye.



The more complete answer is this though:

Theoretically, DxO would have to define a single SNR value which incorporates all aspects, like dynamic range, gray level noise, color sensitivity etc. And plot this single SNR curve against ISO and derive a score like ISO where a threshold is met. And it should use two thresholds: 30 dB (as it does now) and 24 dB which is much closer to real sports photography.

But this combined curve is not defined. Rather, DxO defines three thresholds: SNR, DR, color sensitivity. Whichever threshold is met first defines the sports iso. Most of the time, this is the SNR value. But not always. This is a reason why the sports iso score sometimes can look erratic. And in fact it is. So, depending on which threshold is met first, the overall score is dominated by 18% gray noise, DR or color sensitivity.

However, if you trust DxO's wisdom, the sport's score is an ISO value beyond which you see enough image degradation to care about.
11-09-2010, 02:13 PM   #71
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And to simplify the meaning of the DXO Sports score even further, it represents the highest ISO you can use in order to still shoot top quality images with your camera.

It's worth noting that as your ISO goes higher past that Sports score ISO, you will only progressively start to lose image quality. So you could still be shooting high ISO and still have decent image quality if the camera has a good sensor and can hold onto an OK degree of image quality as ISO increases. However some cameras lose image quality more quickly than others as they go into higher ISO's, which you can see in the DXO charts.

What you can't see directly in the DXO charts is the fact that some camera sensors are better than others at holding onto resolution and detail as ISO increases. That's pretty important too. It can mean, for example, that at high ISO's if it has a good sensor a 12MP camera may be able to deliver sharper images than a 18MP camera with a poor sensor can.
11-09-2010, 03:14 PM   #72
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I hope it's as good as the K-X or I just waisted $250.oo by ordering a K-R over the K-X for my wife. The main reason I odered the K-R is that she likes the lighted focus points in the K-R.
11-09-2010, 04:05 PM   #73
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QuoteOriginally posted by Fl_Gulfer Quote
I hope it's as good as the K-X or I just waisted $250.oo by ordering a K-R over the K-X for my wife. The main reason I odered the K-R is that she likes the lighted focus points in the K-R.
I don't think you'll regret it. Looks like there's a lot of incremental improvements.
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